I don't think it ever occurred to me that enrolling as the first and only Western student in a Chinese chef's school was a difficult or a strange thing to do. It was an impulsive decision, like going to China in the first place. I wanted to learn more about Sichuanese food, and I didn't even consider as an obstacle the fact that I would have to study in Sichuanese dialect, in a big rowdy class of boys who weren't necessarily going to accept me.

Of course I had been used to sharing my family home in Oxford with foreigners, and to negotiating cultural difference on a daily basis. It had been no surprise to come down to breakfast and find a Sicilian engineer or a Turkish porcelain tycoon drinking coffee with my parents. Family camping holidays around the British Isles or Europe were never very organised. My father plotted our routes, choosing roads on the basis that they appeared as wiggly lines on the map and were therefore likely to be scenic. We rarely had a firm idea about where we would stay, and often had to pitch camp spontaneously by the side of the road.

The same applied to living in China in general. The country was still in the stranglehold of the decaying communist system. Stuffy bureaucrats made key decisions in every state-run institution and state-owned restaurant. If you obeyed the rules and tried to make arrangements through official channels, whether they were for a cooking lesson or a trip to a forbidden part of the country, you would be thwarted at every turn. Everything would be impossible: the system, it seemed, was designed to say 'no'. Yet in other ways, China was positively anarchic: anything was possible. You just had to improvise.

In China, my travelling was similarly open-ended. I would just have the thought of going to a particular place, and then go there, without paying any attention to logistics. This was probably the only way to deal with China in the mid-nineties, because if you did stop for a moment to consider the horrifically dangerous roads, the joltingly uncomfortable buses, the hassle from the police and the long hours it took to get anywhere, you would be unlikely to venture out at all.

I spent most of my holidays in China travelling into fei kai fang di qu ('areas that are not open'). I had to use subterfuge to buy bus tickets, to travel before dawn, and to disguise myself, on several occasions, as a Chinese peasant. Upon arrival in a forbidden area, it became a matter of persuading minor officials and policemen to do things that were against their better judgement. Mostly, they were flummoxed at being faced with a friendly twenty-something Englishwoman chatting merrily to them in Chinese. They would offer me tea and cigarettes, listen to my charm offensive, and eventually agree to waive the fine, let me stay for a little longer, or allow me to take photographs of the local monastery. I was always aided in my outrageous negotiations by the fact that communications in remote areas were lousy: the doubtful policeman would invariably try to telephone his superiors in the nearest town for advice on how to handle the crisis, but the lines were always down. It was just him versus me.

In my twenties I relished the challenge of this cloak-and-dagger travel. It was fantastically exciting for a start, wandering off into Tibetan counties that had barely seen any foreigners since the early twentieth-century missionaries. Strange though it may sound, I also adored the sport of my skirmishes with the Chinese police. I was not a Tibetan, who might be sent to a prison camp on trumped-up political charges, or a peasant at the mercy of the vagaries of some local official. I knew enough about Chinese political sensitivities to avoid doing anything stupid. So there was nothing at stake: the worst that might happen was that I might be fined and packed off back to Chengdu.

Liu Yaochun and I first met when we were fixed up together as conversation partners by the history faculty at Sichuan University. Most of my foreign student friends were introduced by their teachers to dull language partners, with whom they had a few strained conversations about cultural differences before deciding to abandon the experiment. But Liu Yaochun was different. The elder son of two illiterate peasants from one of China's poorest regions, he had managed to win a place at Sichuan University by sheer brainpower. By the time I met him, he was already embarking on the postgraduate history degree that would lead him into a career in academia. (To me, he always seemed like a human advertisement for the social mobility created by Chinese communism.) He turned out to be fantastic company: original, funny, and full of ideas. We spent many hours talking to each other in a wild mix of English and Chinese, about history, culture, politics, philosophy, morality and religion. It is to him that I owe most of my Chinese language skills, and he says the same about me with reference to his English.

So I became brazen in my attitude to China. I just went ahead and asked, fully expecting everything to fall into place as I wished, somehow ('La Principessa', my Italian friend Francesca called me). And as often as not, the initial 'no' became 'yes'. It was hard and time-consuming work to make things happen, but then I had the time, and the youthful energy, not to care.

Studying at the Sichuan cooking school, battling against the chauvanism of my classmates and struggling with the language of professional Chinese cookery, was just another of the bizarre adventures I was encountering so often that they had come to seem an entirely normal part of life. By then it didn't require any particular courage or determination. I just got on with it. Far more difficult, in a way, was the time I spent with my friend Liu Yaochun and his family, passing the Chinese New Year in their remote village in the north of China.

My first visit to the village where Liu Yaochun had grown up was a culture shock, despite my growing familiarity with China. I had leapt at the invitation to spend the Lunar New Year with his family, and made my way there on a series of trains and long-distance buses. The village lay in a distant corner of northwestern Gansu Province, not far from Inner Mongolia and the northern fringes of the Chinese empire. It was midwinter, and freezing cold. The white, wintry sun hung over a bleached landscape, eerily bland, devoid of feature and colour. Monotonous, pale, dusty hills rose to the north; the pale dusty fields were bare; and the houses were built out of the same pale earth as the land on which they stood. Even the poplar trees, leafless in winter, were covered in dust, and the sky was so feeble a blue that it looked scarcely different from the land. It made me feel desolate, this monochrome emptiness.

Liu Yaochun was a Cultural Revolution baby, born in 1970. When he was small, he lived with his parents, and, later, his brother and sister, in a single-roomed village house built of mud bricks, with an earthen floor. The land his parents farmed was dry and dusty, the northern winters harsh. His primary school was another mud hut, and there was little to eat most of the time besides dried sweet-potato chips that were sent as famine relief by the authorities. But Liu Yaochun was clever and hard-working, and he swotted away in his mud hut, learning his Chinese characters and doing his sums. His parents, knowing that a good education was his only chance to escape a life of peasant drudgery, sent him to high school in the nearby county town, where he lodged with an aunt and uncle. Six years later, at the age of eighteen, he passed the national university examinations and matriculated at Sichuan University, one of the best in China.

Although his parents were still in their forties, they looked older, worn out by a life of gruelling agricultural labour. They had lived through the tumult of land reform, famine and the Cultural Revolution. (Liu Yaochun's father, with an embarrassed grin, recalled his fatuous political activities during those years -- like dancing the 'loyalty dance' to Chairman Mao, which involved skipping around the outline of the Chinese character for 'loyalty' on the ground.) Because they couldn't read, and spoke a thick local dialect, travelling was difficult for them. The furthest they had been from the village was to the provincial capital, Lanzhou -- and even that was adventurous by the standards of most of their neighbours.

Liu Yaochun's parents no longer lived in a mud hut, but they were still illiterate. Some years before, they had built themselves a traditional home from pine and poplar trunks, bricks and earth: five rooms and a grain store opening on to a walled courtyard. Outside the walls, there was a small orchard, and a shed for the ass. The main room was bright and high-ceilinged, with exposed beams. One end of it was taken up by the kang, the raised earthen platform that is the social centre of rural houses in northern China, beneath which smouldered a fire of animal dung, keeping it constantly warm. We sat on the kang during the day, brewing tea on a wood-fired stove whose tin chimney lurched crazily upwards to a hole in the roof; at night I slept there with Liu Yaochun's mother and sister, each of us wrapped in quilts. The men, Liu Yaochun and his father and brother, slept on another kang, in a room across the yard.

No one in the village possessed a camera, so news of my arrival with an old Olympus SLR slung around my neck had spread like wildfire. Overwhelmed by the villagers' kindness and hospitality, I found myself agreeing to photograph them all.

At that time of year there was little farm work to do, so the men of the village whiled away their days in conversation, drinking sweet black tea and eating watermelon seeds. Since I was the first foreigner to have visited the village within living memory, I was treated as a gui bing, an honoured guest. Everyone wanted to meet me. A village 'intellectual' composed a poem in my honour; the women presented me with pairs of carefully embroidered cotton insoles.

In a neighbour's courtyard, an old woman sat down in a wooden chair, taking her place at the centre of my picture. Her eldest grandson stood behind her right shoulder; her second grandson behind her left. The last and youngest grandson, a naughty little boy of five, squirmed with impatience as his parents positioned him between his grandmother's knees. Then there was silence, a moment of seriousness, and I clicked the shutter.

I started taking my pictures casually, but quickly realised that I was documenting a moment in the history of the village, its social hierarchies and tight family units. The old woman's grandsons were known, according to Chinese tradition, as lao da, lao'er and lao san -- oldest, second oldest and third oldest. She had several granddaughters too, but, being female, they didn't count in the family hierarchy. They huddled together on the periphery of the courtyard as their brothers posed, excluded from the photograph just as they were excluded from the family lineage.

The grandmother sat regally at the centre of the photograph. Behind her, and beyond the curtain that hung over the main door of the house, a black-and-white image of her deceased husband presided over the family shrine, a constant reminder of the social supremacy of the older generation. The old lady's sons and grandsons were expected to kowtow before this image when they entered the room, and to burn incense and ghost money for their ancestors at every festival. When the old woman died, her photograph would be placed there too.

With Liu Yaochun at my side, I wandered from house to house, courtyard to courtyard, taking the official family photographs: a young woman and the fiancé chosen by her parents; baby sons with penises proudly displayed through the gaps in open trousers; old people posing solemnly for my portraits, perhaps their last. These photographs, the most serious, would be the ones that would grace the family shrines, to be revered by future generations. The old people preferred to be photographed in black and white, feeling it, perhaps, to be a more ancestral medium.

And then there were the people I didn't photograph. The madman who had lost his mind when his wife died and his 'cradle-to-grave' state job was taken from him. He crouched by the side of the road, rocking gently on his heels, lost in reverie. The illegitimate child whose mother had run away to the city because of social ostracism. And, of course, the baby girls.

I felt awkward as a female visitor. Liu Yaochun's mother and sister did all the household work. While the men and I lazed around on the kang, smoking cigarettes and chatting, they swept away the fag ends and the watermelon seed husks we had cast to the floor. In the kitchen, they kneaded flour into dough for steamed buns; they mixed flour with water, rolled it and cut it into noodles, or pulled it into ma hua twists. They chopped wood and stoked the fires in the stove and beneath the kangs. At mealtimes, they waited on us, and ate their own food afterwards, in the kitchen. Then they washed the dishes. My most strenuous efforts to help were resisted, so I yielded, guiltily, accepting my odd status as an honorary man.

The meals we ate were simple and monotonous; this was not the rich gastronomic landscape of Sichuan, but the arid north, and winter too, when there was little to eat besides wheat, pork, chilli and garlic. Rice was an occasional luxury. Sometimes the staple grain on the table was millet, an ancient Chinese cereal that city dwellers regard as lowly peasant food, but even that was unusual. As my Sichuanese university teacher once said to me disparagingly: 'In the north all they eat is mian (flour-foods).' We sat at the square wooden table in the main room, slurping our noodles or chomping on plain buns, adding crushed garlic or chillies in oil to enliven their blandness. There was little difference between breakfast, lunch and dinner. We ate scarcely any meat, and the only fresh foods were home-grown onions, celery, garlic and apples. After a few days my bowels had turned to concrete.

You have only to visit places like Liu Yaochun's village to realise that the concept of a single 'Chinese cuisine' is rather flimsy. For a start, China is divided, north-south, between the wheat-eaters and the rice-eaters. The inhabitants of Gansu belong to the former, their province part of a great swathe of pasta- and bread-eating territory that extends west from the eastern coast and Beijing to the borders of Central Asia, and even further. Certain northern Chinese pasta forms are strikingly similar to those found in Italy: like the 'cats' ears' eaten in Xi'an, which are identical in shape and manufacture to orecchiette. The Italian folk explanation is that Marco Polo introduced the Chinese to spaghetti and its ilk during his travels in the late thirteenth century, while the Chinese like to think that pasta was a gift they gave to the world. In 2005, Chinese archaeologists claimed to have clinched the argument by discovering a four-thousand-year-old bowlful of millet noodles in a site they excavated along the Yellow River. Many experts, however, believe that the true origins of pasta-type foods lie further west, in Persia.

In the days leading up to the New Year, I watched Liu Yaochun's family make their preparations for the feast. Liu Yaochun was in charge of the Spring Festival couplets: with a calligraphy brush he inked auspicious phrases on to strips of red paper that would be pasted up around every doorway in the house (sometimes it's useful to have a literate son in the family). The fattened pig had already been slaughtered and brined, but his father took the cockerel outside and dispatched it with a cleaver, letting its blood drain out into the dusty earth. In the main street that ran through the village, local lads practised their drumming, and the children made beautiful lanterns out of wooden struts and multi-coloured paper. The girls were dressed brightly in scarlet, fuchsia pink, or red-and-pink, as if to defy the bleached monotony of the landscape.

The elderly are revered in China partly because they are ancestors-in-waiting. After they die, their descendants will (they hope) place their images on the shrine table in the main room of the house, and honour their spirits with offerings. Some of the grander old families in Liu Yaochun's village still possessed ancestral scrolls, family trees illustrated with pictures of the deceased, generation by generation, which traditionally hang over the shrine. Pictures of Mao Zedong may have taken the place of these images and scrolls during the Cultural Revolution, but now they were creeping back, alongside Mao. The Chinese family consists not only of the living, but also of generations of the dead.

Sharing food, in China, binds the living family together, and it is also the ritual that connects those on both sides of the grave. On New Year's Eve, Liu Yaochun's extended family, from the grandparents down to the smallest child, processed to the orchard to invite their ancestors to join in the feast. They knelt on the ground, burning paper money and incense, kowtowing repeatedly, pouring libations of strong grain liquor into the earth. The uncles lit strings of firecrackers that shattered the air. Then everybody trooped over to the house of the eldest son, Liu Yaochun's uncle, where the men kowtowed before the main family shrine. The women had laid out a New Year's Eve dinner for the dead: little dishes of meat and vegetables, a bowl of noodles with chopsticks, cups of tea and wine.

One of the peculiarities of the Chinese world of spirits and ancestors, for a foreigner, is its close resemblance to the earthly world. Chinese gods hold bureaucratic sway in their heavenly offices, considering petitions from mortal beings and accepting gifts and bribes much as communist officials do down below (and as imperial officials did before them). Dead people need material things just as the living do: clothing, money, and, these days, even mobile telephones. At funerals, relatives of the deceased burn paper effigies of all these objects, sending them heavenwards in a cloud of smoke. Special shops for mourning goods sell cars, washing machines, watches, and mobile phones, all made out of cardboard and coloured paper.

The tombs of the wealthy were, in the past, well equipped for life beyond the grave. Most famously, the great, brutal unifying first emperor of China, Qin Shi Huangdi, was laid to rest with an entire terracotta army to protect him. My favourite Chinese tomb site, however, is at Mawangdui, near the Hunanese capital, Changsha, where a marquess was buried with his wife and son in the second century BC. The tombs were unearthed in the seventies, their contents in a state of almost miraculous preservation. This noble family was interred with scores of wooden figurines: servants to wait on them and musicians to entertain them. There were wooden models of chessboards and make-up boxes, musical instruments and luxurious gowns, and sophisticated medical and philosophical manuscripts painted on silk. There was also plenty of food, because, above all, the dead need to eat.

The Marquess' wife was buried with a whole last supper of real food, laid out on a painted lacquer tray. Five cooked dishes had been prepared to whet her appetite, along with skewers of barbecued meat, a bowl of grain, cups of soup and wine, and a pair of chopsticks. There were painted lacquer wine cups inscribed with the phrase 'Gentlemen, please drink', and extravagant serving dishes. There was also a store of raw ingredients: many different grains, beasts and fowl, fruits, eggs, millet cakes and medicinal herbs that included cassia bark and Sichuan pepper. A burial inventory inscribed on bamboo strips recorded flavourings such as malt sugar, salt, vinegar, pickles, fermented sauce and honey, various dishes and soups and some ten different cooking methods, among them barbecuing, boiling, frying, steaming, salt-curing and pickling.

Across the Chinese empire, people took care to satisfy the appetites of the dead. In the Astana Tombs of Turpan, on the edge of the Taklamakan desert, archaeologists have unearthed jiao zi dumplings in Tang Dynasty graves: a little dry and brittle, perhaps, but in all other respects exactly what you might have for lunch in the same region today, 1200 years later. The early twentieth century European explorer Aurel Stein returned from the same region with not only the priceless Dunhuang manuscripts, but also some 'jam tarts' and other pastries from the Astana tombs, which still lie in a vault in the British Museum. In Shaanxi Province in the Ming period, people were buried with miniature ceramic tables, laden with dishes of food modelled in clay: sheep's heads, whole chickens and fish, persimmons, peaches and pomegranates.

People in contemporary China often feed their recently dead relatives in a way that seems to emphasise their closeness to the living. They might lay little dishes of cooked food by their graves, home-smoked bacon, green beans and rice, whatever the rest of the family is eating, so the deceased seems to take part in a shared household meal. For long-dead ancestors, the food offerings on the shrine may be more abstract: a whole smoked pig's head, perhaps, or an unpeeled pomelo, neither of them immediately edible. In China, the worst thing you can do to a corpse is dismember it. Ghosts need their legs for walking, and their eyes for seeing. And their stomachs must be filled.

On New Year's Day, Liu Yaochun and I continued with our exhausting round of visits, paying our respects in every house in the village, from dawn to dusk. The food we were offered was lavish by comparison with everyday fare, but varied little from home to home. We nibbled watermelon seeds and walnuts, dried persimmons, peanuts, tangerines, and sweets wrapped in cellophane. Then there were the main dishes: slices of pig's liver and pig's-ear terrine; braised pork ribs; pork slivers stir-fried with celery or green onion; pretty slices of a pork-and-egg roll; steamed porkballs studded with ricegrains; and whole river fish (an obligatory New Year's treat because 'having fish' -- you yu -- is a pun that also means 'having plenty'). The staple foods were sweet-potato noodles, wheat noodles, and little steamed buns, served with pickles, chilli and garlic. Each table was laid with nine bowls, arranged in a square.

If a family elder entered the room, in whichever house we were visiting, Liu Yaochun and the other boys and men leapt to their feet and kowtowed before the family shrine. Liu Yaochun's knees were dusty with all these prostrations. One bearded grandfather we met wore a huge, rough sheepskin over his Mao suit and carried a wooden staff. He told Liu Yaochun he had discovered a miracle medicine. 'It is made with the charcoal from under the kang,' he said, 'and it can cure many diseases, including AIDS.' He handed Liu Yaochun some lumps of coal wrapped in paper. 'Since you are a research student at a university, perhaps you could investigate its scientific properties?' As Liu Yaochun pointed out to me later, 'this project has nothing to do with my major, which is medieval European history.' But in this place of reverence for the elderly, he listened carefully to the old man, nodding solemnly at his every word.

Over the days, I met almost everyone in the village. There were the descendants of the former landlord, whose fortunes had been dramatically reversed in the land reforms of the fifties, but who were now clawing back their relative wealth with a successful minibus business. We exchanged pleasantries with the local communist party secretary, and with an old lady who hobbled around on tiny bound feet, encased in miniature black cotton shoes (the Nationalist government outlawed footbinding in 1911, but it persisted for years afterwards in out-of-the-way places like this).

We also called on a family with six daughters and a baby son. It was illegal, of course, to have so many children, but they had a relative in the local government who had forged a sterilisation document for the mother as a special favour. With so many mouths to feed, the parents were desperately poor: they had even been compelled to give away daughter Number Five for adoption. But they needed a son, badly. Daughters, in the traditional Chinese scheme of things, married out into other villages, so they were useless as pension schemes and future feeders of ancestors. ('My brother and I will have to support my parents in their old age,' Liu Yaochun told me, 'Because in the end, my sister doesn't really belong to the family.') Now, finally, after all these unlucky girls, they had a little emperor, plump and beautiful in his tasselled silk hat. The relief of everyone in the family was palpable.

On the evening of the third day, we ate oversized jiao zi pork dumplings for supper, according to local custom, dipping them in soy sauce and vinegar. After nightfall, loud drumbeats drew us out into the street, and we spied the tail end of the New Year procession, wending its way up a nearby hill. It was an old tradition that had recently been revived -- such 'feudal' customs were banned under Mao. We ran to catch up. The air was electric with the clash of gongs and cymbals, and the frenetic beating of the drums. Homemade paper lanterns, lit by candles and held aloft on sticks, cast a flickering light over the shadowy crowd of figures and the jerky undulations of a dancing lion. The atmosphere was raw and wild.

Perhaps they had visited the only village temple to which women were admitted, to implore the local gods to bring them sons. The side walls of this curious shrine were lavishly decorated with a landscape scene in relief, covered in green-painted hills and grottoes. All over it were colourful little plaster figures of boys in any number of poses, each brandishing a tiny clay penis through a gap in his painted trousers. When Liu Yaochun and I paid a visit, the old man who watched over the temple gave us a tour. 'The women, they break off the penises and eat them,' he said, 'And then I give them a piece of red thread to tie around their necks. It's very effective.'

The procession reached its climax outside the main temple of the village, at the top of a hill. Lights blazed beyond the open doors of the shrine. Firecrackers exploded in a blitzkrieg of light, illuminating the crowd like a photographic flash. Everyone was burning incense and paper money. The drumbeats became louder and more insistent. Boys lit fireworks that rocketed off in unpredictable directions, whooshing into crowds of small children -- one exploded next to my ear, and almost deafened me.

Then the drumbeats took a slower pace and a young girl, the village beauty, stepped out, wearing a ceremonial 'ship' made from brightly coloured paper, decked in rosettes. An 'old man' in a battered straw hat and a false beard made of horse hair (actually one of the village lads) led the 'ship' in a gentle dance, to uproarious laughter. Then the lantern-bearing boys joined in, and their coloured lights wheeled around in the smoke and incense. People yelled and whooped in the mayhem. We were all muffled up against the searing cold.

Day after day, I was paraded around the village like a zoo animal or a celebrity, a real flesh-and-blood foreigner, just like those the locals had seen on their crackly black-and-white TVs. ('I just had a conversation with a Foreign Devil!' whispered one man to Liu Yaochun, after meeting me.) I was forced to eat vast quantities of noodles, dumplings and pig's-ear jelly, and I talked myself hoarse in polite conversation.

One evening we piled on to a tractor cart, swaddled in sheepskins, and went to a richer neighbouring village to see their New Year celebrations, which were famously lavish. Young men in silken robes and heavy make-up performed elaborate dances; there was an open-air staging of local opera. Sick of being the centre of attention, I wore dark glasses and swathed my head in a woollen scarf. But at the end of the evening, when I climbed back on to the trailer with Liu Yaochun and his uncles, I removed my disguise. Suddenly, a crowd materialised around us, and actually chased us out of town. Someone shouted after the tractor: 'Please! We live in the countryside! We never see any foreigners! Please bring her back!'

Later the procession left the temple and called on every house in the village, pouring into each courtyard in a rush of light and colour. Firecrackers rent the air, driving away evil spirits. Family members burned offerings at their ancestral shrines, and rewarded the dancers and the drummers with gifts of fruit and nuts. A sick woman knelt on the ground as the lion danced around her, and flaming ghost money was passed over her head. A paper lantern caught fire and withered in a blaze of light. Overhead, the new moon was a sliver of light amidst a glittering canopy of stars.

After the ceremony I was roped into what I can only describe as a kind of press conference. I was invited to sit on the kang in a side room, and the wedding guests crowded in to look at me. There were people trying to push in from the courtyard, craning their heads around the door, peering in at the window. The air was hazy with cigarette smoke.

Shortly before I left the village, we were invited to attend a wedding, where a large, buxom young woman was entering into an arranged marriage with a slender young man whom she hardly knew. We watched them light the wedding incense, and make their bows to the gods, their parents, their ancestors and, finally, to each other.

Someone took it upon himself to be the master of ceremonies, inviting members of the audience to quiz me. 'How can England be a democracy when it has a Queen?' asked someone. 'In your opinion is it better to have straight or curly hair?' demanded another. The eyes of one man widened in concern and amazement when I told him that Winston Churchill was dead. I felt a heavy sense of responsibility. To many of them, apparently, I was the outside world. I was the diplomatic representative not only of her majesty Queen Elizabeth, but of the nations of Europe, the United States of America, everywhere that wasn't China. So I tried not to laugh at the more ridiculous questions, I tried my best to answer seriously.

My reward for this exhausting Q&A session was a seat of honour at the wedding feast: a lavish spread of chicken with ginger, slow-braised belly pork, eggs and tomatoes, fried pork with spring onions, potato chips in honey sauce and whole fried fish. It was an incredible menu for rural Gansu in midwinter. The bride and groom made their rounds, toasting everyone with strong grain liquor. Enamel dishes of cigarettes lay on every table and the men smoked furiously, tucking extra cigarettes wherever they could -- in jacket pockets, behind their ears.

By the end of the day I was succumbing to a rotten cold. Walking home with Liu Yaochun, I burst into tears. I couldn't help it: I was ill, I was tired, I was lonely. I had exhausted all my reserves of patience. I was sick of being a foreign diplomat, of having people nodding sagely at my every trivial utterance as if I was expressing the wisdom of Confucius. And I was desperate for privacy. All those nights on the kang, sleeping alongside the women of the family and occasional female visitors. The visitors watching, fascinated, as I poured hot water into the basin on the washstand in the morning, washed myself, dressed and undressed. Even when I went to the loo, on a designated patch of earth next to the orchard, I had to perform under the gentle scrutiny of the family's ass.

Perhaps I was also feeling the weight of tradition on my shoulders. After two weeks in the village I was being sucked into its patriarchal vision, and it was one in which people like me didn't exist. Although only in my mid-twenties, I was already antique by local standards. The only other unwed woman my age I met, Hong Xia, was being married off in a few months to a man she barely knew, who lived in an even more impoverished village. She was dreading her wedding, but knew that if she waited any longer she wouldn't be able to find a husband, and the old village gossips would start to wonder if there was some sinister reason for her solitude.

And then there was the disturbing matter of the Hungry Ghosts. In China, the worst thing you can do is to leave no descendants to honour your memory. The spirits of the childless, neglected and unfed, are malignant. They wander the earth looking for mischief, venomous in their hunger. During the seventh lunar month, the Ghost Month, the gates of the underworld open and the spirits of the dead pour forth. It's an inauspicious month, a bad time to move house or marry. It's a time when people make renewed offerings to their ancestors, serving them dinner and burning effigies of all the things that they might need in the coming year. But they take care not to forget the marauding Hungry Ghosts, who must be appeased by rice thrown into the sacrificial fire.

Liu Yaochun was furious with me for weeping. 'Someone might see you!' he said, 'And then they will think that my family are mistreating you! We'll lose face in the village.' I was furious with him for caring so little about my feelings. It was the only serious altercation we had ever had.

People in China normally greet a young woman by asking her, first, if she is married, and then how old she is. If the answer to the first question is no, and to the second is more than about twenty-three (in a village like this), the response is a sharp intake of breath, and an expression of incredulity. Day after day, in this remote community, I was reminded that my whole life was invalid unless I married quickly, and reproduced. The Hungry Ghosts hovered in the background, menacing. Would I end up as one of them, I asked myself, roaming the streets of Oxford, yearning for sustenance, hoping that my nieces and nephews would remember to feed me?

Perhaps it was all this that made me so glad to return to Sichuan after the Chinese New Year. My stay in Liu Yaochun's village had been fascinating, but I certainly didn't want to live there. Chengdu, with its spirited women, gentle climate and marvellous food, felt much more like home. Liu Yaochun and I travelled back there together at the end of the holiday, on the long, slow train from Lanzhou, winding our way through the mountains as we philosophised endlessly and sipped from our mugs of green tea.

But the end of my course at the Sichuan cooking school turned out to be just the beginning of a project that would take over my life. Back in London, I left the BBC and spent a year at the School of Oriental and African Studies, reading for a masters degree in Chinese studies and writing my final dissertation on Sichuanese food. My first proposal for a Sichuanese cookbook was rejected by six publishers, and after my course had ended I returned to work at the BBC, this time in radio. Living in London, I cooked my favourite Sichuanese dishes for various English friends, and the reception was often ecstatic. No one had ever tasted Chinese food like it before, so spicy and exciting. I was astonished by the absence of authentic Sichuanese restaurants in a city as diverse as London, and the near-total lack of Sichuanese recipe books in the English language.

Towards the end of my time at the Sichuan Institute of Higher Cuisine, I began to think seriously about writing a Sichuanese cookery book. And I knew that if I wanted to do it, I had to go back to England, at least for a while. I was also running out of money, and needed to decide whether or not to return to my old job at the BBC. So, when my cooking course ended, I said farewell to my teachers and my fellow chefs, not knowing when I would see them again. I packed up my possessions, and sent home many boxes of things that seemed terribly important at the time but turned out to be useless in England, like Chinese army plimsolls, bamboo ornaments and thermal underwear. And then I left Chengdu, with an aching heart.

After a year, I thought I would give the book one last try, so I wrote a much better proposal, and to my delight was offered a publishing contract. Thanks to the support of various BBC managers, I spent many months in Chengdu over the following three years, continuing my research. And whenever I stepped off a plane or a train into the damp Sichuan air, smelt the chillies and Sichuan pepper, and heard again the languid tones of Sichuan dialect, I had the same glad feeling of returning home.

Liu Yaochun and I, of course, continued to spend whole afternoons and evenings talking in teahouses. But he never shared my culinary passions. Liu Yaochun has always been a puritan when it comes to food. He grew up in the hard north, after all, on a diet of sweet potatoes, steamed buns and noodles, and he tut-tuts at the dietary promiscuity of the southern Chinese: 'They eat so many weird things. It's revolting. I really think there should be limits.' The amusing thing about our friendship is that, through me, he has found himself invited, over the years, to endless banquets in the finest restaurants in Chengdu. He acts as interpreter for foreign journalists on gastronomic tours, and is on friendly terms with some of the best chefs and cooking teachers in the city. 'I'd really be just as happy with a bowl of noodles,' he says with a self-deprecating grin, sitting down to another stupendous feast.

Over time, I met an increasing number of Sichuanese chefs and food writers, and was welcomed into culinary circles. People began to invite me out for the kinds of banquets I'd only heard about as a scholarship student and a trainee chef. I attended a food history conference where we barely had time to give our papers before we were ferried off, at the end of each session, to another fabulous restaurant.