Sichuan pepper, flower pepper, prickly ash, hua jiao… It is the original Chinese pepper, a native spice used long before black pepper stole in over the tortuous land routes of the old Silk Road. It is also the space dust of the spice world. An unexpected first encounter with it can be disconcerting, to put it mildly. I offered some to a stranger, once, at the annual Oxford Food Symposium, without a word of warning: he thought I was trying to poison him, and hasn't spoken to me since. Actually, I should have been more careful, remembering my own first experience of Sichuan pepper, during a visit to Chongqing in 1992. 'The dishes were all flavoured with a particular spice which I found utterly unpalatable,' I wrote in my diary. 'It tasted like a powerful combination of aniseed, lemongrass and chilli and numbed my mouth with an unbearable taste. I ate very little other than soup and rice.'

The air in the orchard has a mesmerising, citrussy smell. The pimpled green berries, just beginning to blush pink, cling in ones and twos to the thorny stems of the trees. Despite the drizzle and the grey sky, I'm elated. I pluck a pair of peppercorns and rub them in my hands. The fragrance comes quickly, perfuming the air around. It is overwhelming, so fresh and zesty, so redolent of wood and wildness. I close my eyes. And then I put some pepper between my lips. In its green astringent newness, it puckers my tongue immediately, and then, a few seconds later, the tingling hits. That incomparable tongue-numbing sensation of Sichuan pepper, a fizzing that starts stealthily and rises to a mouth-streaming, breathtaking crescendo that can last for twenty minutes, before it slowly, gradually dies away. It is stronger even than I expected, and I laugh in surprise. For years I have dreamt of tasting Sichuan pepper on the tree, and here I am, in Qingxi itself, my lips singing.

I smile to read that now, knowing how the gentler cooking of Chengdu turned me into a Sichuan-pepper addict. And I have developed a better strategy for introducing it to other people. Psychological preparation is essential ('Are you sitting comfortably? Then let me explain…'). Instructions must be followed precisely. 'Put this pepper husk into your mouth, chew it two or three times at the front of your mouth and then spit it out immediately! Do not carry on chewing, wondering why nothing is happening, or it may overwhelm you (the tingling sensation takes a good ten seconds or so to develop). Now sit back and wait!' This more subtle approach tends to win people over, if only because of the wild novelty of the sensation, and I've seen many of my friends succumb to its charms.

In all my years of research for my Sichuanese cookery book, I never actually saw a Sichuan pepper tree. For that, you have to go to the high, dry slopes of various places in northern and western Sichuan. But of all the pepper grown in the province, none is better than that of the remote county of Hanyuan in the southwestern mountains, and within Hanyuan County itself, nothing compares to the sumptuously aromatic pepper of Qingxi Township. Even within Qingxi there are finer distinctions for aficionados: if you want to reach the very pinnacle of peppery perfection, you must accept nothing less than pepper harvested from the trees of niu shi po, the Ox Market Slopes, at the village of Jianli just outside Qingxi itself. Once, this pepper was sent in tribute to the imperial court. 'Qingxi Tribute Pepper', they still call it here.

I'm not sure why it took me so long to go to Qingxi, when I'd wanted to for many years, but I only made it there, for the first time, in 2001. Most of my Chinese acquaintances would have baulked at the idea of accompanying me on a gruelling journey into the impoverished backwoods of the province, but one old friend, Mu Ma, was game. So, one morning in June, we set off from Chengdu by long-distance bus on the hard eight-hour ride to Hanyuan County.

I met Mu Ma in the course of my food investigations in Chengdu, and we hit it off immediately. He's an academic who spends his time travelling around remote villages in south-west China, researching and documenting traditional crafts and rituals before they disappear. Since knowing me, he's taken more of an interest in beancurd workshops, kitchen ranges and bakeries. Mu Ma's shaggy black hair always looks untidy, even if it's just been cut. He speaks in Chengdu dialect, and teaches me local nursery rhymes, like the Sichuanese equivalent of 'Jack Sprat and his wife':

Ni chi fei, wo chi shou (You eat the fat, I eat the lean)

Cai ban shang (On the chopping board)

Qie la rou (Slicing the bacon)

Yao mei ken gu tou (Little sister can gnaw on the bones)

Mu Ma doesn't give a damn about karaoke and fancy restaurants. When he's on the road, he takes very little with him besides a toothbrush, and stays in the most basic kind of guesthouse. He seeks out archaic teahouses and restaurants, old-fashioned printing houses and dilapidated monasteries; and spends hours in conversation with pedlars, peasants, and artisans.

When we finally arrived in Qingxi, we were accosted by a band of raggedy children, who, excited by this outlandish visitor who said she'd come in search of pepper trees, whooped and laughed as they led us through the lanes. The village houses were ramshackle, higgledy-piggledy, their wooden gateways leading into courtyards stacked with old pots and pans. Sun-bleached corncobs and dried chillies hung from the eaves. Beyond the last houses lay the pepper orchard where I had my first taste of the fruit.

You fei you you shou (There's fat and there's lean)

Sichuan pepper is one of the spices mentioned in the ancient Book of Songs, where its shiny and abundant seeds are a symbol of fertility (a seed and a son sound the same in Chinese: zi). 'Pepper houses' (jiao fang), they used to call the chambers of Han Dynasty imperial concubines, because the spice was mixed into the mud used to plaster their walls, in the hope that the women would produce sons and heirs. Rural people exchanged bunches of Sichuan peppercorns as love tokens; the spice is still imbued with erotic symbolism because of the way its berries hang in pairs, like testicles. Even today, in remote parts of Sichuan Province, peppercorns are thrown over brides and grooms, an aromatic confetti.

In another month or two, the children told us, the peppercorns would be dark pink all over, dried by the hot sun, and they would split open to reveal their seeds, black and shiny like the eyes of birds. The young men would then strip the peppercorns from the branches, gather them in bamboo baskets, and lay the split, pimpled berries out in the sun to dry. When they were ready, the local girls would sit on their doorsteps, woven bamboo baskets on their knees, tossing the peppercorns to shake out their tasteless seeds, saving the aromatic husks.

After my first, striking taste of the fresh pepper, Mu Ma and I left the orchard with our retinue of children, and entered the gates of the Confucian temple opposite, a derelict timber-framed mansion. Once, it must have been splendid; now, it barely whispered of its former glory. A little bridge led over an ornamental pond, but the heads of the statues on its stone balustrades had been knocked off by Red Guards during the Cultural Revolution. The old temple hall had been brutally boarded up and carved into utilitarian rooms, and there were faded revolutionary slogans on the walls. Moss and weeds grew among the flagstones, and the paint on the buildings was peeling. We discovered it was being used as a social centre for the elderly, and on that day they were having a feast, so a dozen round tables had been laid in the courtyard.

The pepper is also a medicinal herb. It was unearthed in the grave of the Han Dynasty noblewoman found at Mawangdui; accompanying prescriptions written on silk advised its use in treating ulcers. It is thought to be a stimulant and diuretic, good also for relieving flatulence and encouraging digestion. Moths and other destructive insects shy away from the pepper's powerful aroma, so it is traditionally used as an insect repellent in wardrobes and granaries. Ingested in large quantities, it is severely toxic -- which is why several ancient texts mention its use as a means of forced suicide.

As I entered, a flock of old ladies and men rushed up to me, beaming. 'Miss Rose, welcome!' They behaved as if they knew exactly who I was. At first I was perplexed by their familiarity before it dawned on me that they must be thinking I was Rose Acock, an Englishwoman who had been running poverty-relief projects in rural Hanyuan for years. I had never met Rose, but we had been in email contact once or twice. There clearly hadn't been any other Englishwoman in Hanyuan for a while, let alone another named after a flower. 'I'm not Rose, I'm Fuchsia,' I found myself explaining a hundred times. The villagers were astonished to hear this, but no less friendly.

Mu Ma started inspecting the few temple relics: a worn stone tablet inscribed with Chinese characters; an elaborate, dragon-coiled basin for burning incense. Some old ladies stood around him, telling stories of the place. After a while I became aware of a couple of khaki uniforms mingling with the villagers in the temple. They loomed closer, and soon I had a policeman at my side, studiously casual. He watched me as I scribbled in my notebook. Then he asked me for my ID. I rummaged in my bag for my passport. He made a big deal of his scrutiny, giving me a sly, disconcerting smile. I began to feel nervous. As far as I knew, there was no reason why I shouldn't be there. But the policeman was intimidating, and long years of experience of such things had taught me that it was best, in such situations, to play humble.

'What are you doing here?' he asked.

I realised as I said this how absurd it must sound. Sichuan is internationally famed for its tourist attractions: the giant Buddha at Leshan, Mount Emei with its 'sea of clouds', and the coloured lakes of Jiuzhaigou. Two hundred years ago, Qingxi was a flourishing transport hub on the cha ma dao, the 'tea-horse way' that connected inner China with Tibet and India; now it was a forgotten backwater. What would the policeman make of a foreigner who chose, instead of Jiuzhaigou, a trip to a shabby town in one of the most impoverished counties in the province?

'I've come to see the Sichuan pepper trees.'

'This isn't a closed area, is it?' I asked. He just gave me a hard glance, handed back my passport, and continued to observe me as I walked, self-consciously now, around the temple. He assigned a young policeman to watch over me. Barely more than a teenager, lanky and awkward in his uniform, this boy was plainly unsure what to do with the dangerous alien in his charge. I led him out of the temple and back into the village streets, and he stayed within a metre of me at all times, following me into courtyards, up lanes, and into fields.

'What are you doing here?' he asked me again, with a pointed glance at my notebook and pen.

I couldn't understand the senior policeman's paranoia. Perhaps he was being defensive in that faintly nationalistic Chinese way, reluctant to let a foreigner see the 'backwardness' of rural China. Perhaps he was just a product of his education: thirty or forty years ago, every foreigner was seen as an imperialist spy, intent on subverting the Maoist political system. When we had finished exploring the village, he insisted on giving us a lift in his police jeep back to our hotel in the nearby county town, Jiuxiang. He warned us not to go out.

Of course, as soon as he had dropped us, we left the hotel and went off in search of supper in the old town centre. The main street was an alley of wooden houses with panelled fronts and low-tiled roofs. Some were already boarded up for the night, others were still open for business. A seamstress leant over her puttering sewing machine at a table in the street. There were makers of funeral wreaths, vendors of incense, cigarettes and snacks. Night was falling by the time we stumbled upon the old pai fang, an amazing memorial gateway covered in a froth of extravagant carvings.

We ate rice and vegetables in a crumbling restaurant where the cook shook his wok over the flames of a coal-fired stove. When we finally made it back to the hotel, the police were waiting for us. They left me alone, but interrogated Mu Ma for an hour. They took down the details of his work unit. They asked him, again, what I was doing there. 'It's for her own protection,' they claimed. Some time ago, they told him, a Japanese tourist ran out of money here, stayed 'outside' in a farmhouse, and was murdered. 'It's for her own protection.' I slept uneasily, the sound of the frogs like a ghostly chorus outside.

Before I left Qingxi, I persuaded a villager to give me a small pepper plant, which I planned to take back with me to England. It was a slender thing, bedded in a little earth, swaddled in a plastic bag. I carried it back with me to Chengdu, where I cared for it tenderly, and then to Beijing. But at Beijing airport I had a sudden crisis of conscience. Britain was engulfed in the foot-and-mouth epidemic, and there was a crackdown on the import of fresh foods and agricultural products. I was afraid of being caught with my pepper plant. And so I left it, forlorn in its wrapping, on a table in a Beijing airport cafeteria. I thought about it all the way home, and for weeks afterwards.

The roads were as bad as I remembered. We took a comfortable modern bus from Chengdu to Ya'an, 'The City of Rain', but after that it was juddering country buses and potholed roads. The landscape was soft and amorphous. The sun shone vaguely through the mist. We crawled up mountain roads, the bus horn honking incessantly, through a landscape of steep terraced fields, green with winter vegetables, bordered by bamboo and pine. Little frothy cataracts spilt down from the heights to the boulder-strewn river bed, far below.

Five years later, Mu Ma and I returned to Hanyuan in midwinter, just before the Chinese New Year. I had been in Shanghai for a few months, exploring the tastes of eastern China, and was hankering for mountains and wild open scenery. And I'd wanted for a long time to go back to Qingxi, to find out more about my most beloved spice.

Higher and higher we climbed, the bumpy road clinging to craggy hills. There were precarious patches of cultivated green on even the highest slopes, farmhouses nestling amid plumes of bamboo. In the coal-mining area near Yingjing, we passed a ramshackle workshop open to the street. Everything in it was covered in a thin layer of coal dust, including the old man working there with pieces of metal. It looked like a scene from an old black-and-white film, except that there amid his grimy pots and pans, on a grimy chopping board, was a single lettuce, so vividly green that it appeared to glow. We juddered past, honking. Processions of lumbering trucks passed us. Some old men in army-issue greatcoats and fur hats with ear-flaps played Chinese chess outside a teahouse.

The following morning we rose early and went to the bus station, where we haggled for a lift to the village of Jianli where, on the Ox Market Slopes, the finest Sichuan pepper is said to grow. Eventually we agreed a price with the driver of another loaf-of-bread van, a jovial man with round spectacles that echoed the roundness of his face. As he waited for a last passenger to fill up the van, we chatted for a while. 'To look at you,' he said to me, 'one would imagine that you are not Chinese. Are you a foreigner?' Later, talking to Mu Ma, he referred to the ying guo xiao huo zi, the 'young English lad'. Staring at him in amazement, I told him that I was actually a woman, and no longer particularly young. The other passengers laughed at him. 'Sorry, my eyes aren't that good,' he said. I sighed as I thought of him driving us along a rutted track into the mountains. But it couldn't be helped. Finally we set off, crammed into the tiny van with a pepper farmer and his daughter, who carried agricultural supplies in baskets on their backs.

As we drove over the last pass before Hanyuan, the mountains were frosted with snow, the pine trees heavy with it, and then we were engulfed by a freezing white mist, dream-like. Finally we emerged into the arid Hanyuan landscape. Barren in winter, the fields were filled with battalions of spiky pepper trees. Just before we reached Qingxi, the way was blocked by a multiple pile-up, so we had to leave the bus, walk past a crumpled mess of lorries, and hitch a lift in the loaf-of-bread van belonging to an insurance company. 'Are you Miss Rose?' asked the driver as he rattled at dangerously high speed over the potholed road.

The valley was flooded with the cool blue-green of winter garlic. Every household around here once reared oxen to plough the land, and the Ox Market Slopes, where we were headed, was where all the beasts from the surrounding area were bought and sold. 'But now people use machines to till the earth,' said the farmer's daughter, 'so they don't keep oxen. It's too expensive to feed them all year round when they are only used for occasional work.' Still, there were a number of specialist beef restaurants along the road, cashing in on their local history.

The Ox Market Slopes lie at 1700 metres above sea level, 200 metres higher than Qingxi itself. And that, said the farmer, along with the dry climate and the sandy soil, was the secret of the famous tribute pepper. We left the van outside the local government office, where a man was practising Tai Chi in the yard, and a black hen pecked. The village head, warming his hands over a charcoal brazier, offered us tea, and then asked a woman who worked with him to take us around. So we tramped through the crunchy snow, and walked through an orchard of pepper trees. 'This area produces about ten tonnes of pepper a year,' said our guide, as we surveyed the prickly trees and the snow-blurred terraces of the valley. 'And it's the finest of all. They call the tribute pepper wa wa jiao, "baby pepper", because each pair of peppercorns also has a pair of tiny, embryonic peppercorns, or "babies" (wa wa) at its base.'

Our driver was still waiting outside the government offices, and there was one more sight to see before we returned to Qingxi. High above Jianli, just off the main road, stood a concrete post proudly emblazoned with the slogan: 'Hanyuan County, the home of flower pepper'. Just below it, less conspicuous, there was an old stone tablet engraved in Chinese characters. This stone is known as the mian gong bei, the 'Tribute exemption stele'. When we had visited Hanyuan five years before, it had lain, in pieces, under a bed in the local government offices, but a dawning awareness of the county's history and its tourism potential had seen it repaired and brought to this prominent spot.

Back in the village, we were invited into a run-down farmhouse by some old women, a great-grandmother and a grandmother, who were looking after a two-year-old child while the wife of the household was out working. They gave us some of their home-grown pepper. 'If you have a stomach ache,' said the grandmother, 'take ten peppercorns in your hands, rub them, and then swallow them with cold water. You'll find it very effective.'

Its worn characters told the tale of how the pepper farmers of the region won protection from the extortions of corrupt local officials in the last days of the Qing Dynasty. At that time, the imperial court demanded an annual quota of pepper in tribute, and its representatives in Qingxi were harsh in their exactions. They squeezed the peasants dry, driving them into desperate poverty. Eventually the peasants could bear it no more, and they petitioned the higher levels of government for mercy. In an act of imperial benevolence, the tribute tax was abolished, and the stone was set up in Jianli as a guarantee of the government's promise.

We piled back into the van and juddered our way to the main road, talking about pepper. And the local official, our guide, let slip that, in a modern version of the old tribute system, 40 jin of the choicest Jianli pepper is bought each year by the Ya'an government, and sent as a gift to Zhongnanhai, the Communist Party leadership compound in the heart of Beijing. 'All these shops,' she said, waving a hand at the rows of little booths along the main road, 'they say they sell tribute pepper, but you can't really find it around here. The best stuff is bought up by officials and people with the right personal connections. Most of what you see on sale here is grown in other parts of Sichuan, and wrapped up in Qingxi packaging.'

Mu Ma and I had lunch at one of the beef restaurants on the main road: a bubbling hotpot that rang and sang with Sichuan pepper. Later, we drove back down to Qingxi. Outside the Confucian Temple that we'd visited five years before, a crowd of peasants in brightly coloured clothes were milling around, negotiating prices for sacks of seed corn. Soon there was a tap on my shoulder. A stocky man told me to accompany him into the government offices, which I suddenly noticed were directly opposite the temple gate. 'Actually, I want to go and look at the temple,' I told him. But it was clear that refusal was not an option. He frogmarched me into the building, and up some concrete stairs into a freezing, smoky office overlooking the seed market. He invited me to sit down, and brewed me some green tea with water poured from a thermos flask.

I braced myself for the usual tedious interrogation. Would he keep me there for hours with his paranoia and political innuendoes? Would he make me write a self-criticism, signed with a fingerprint, like that jittery policemen I'd once met in a Tibetan area of northern Sichuan? Would he assign a teenaged policeman to watch over me? But it turned out that my host, the Secretary of the Qingxi branch of the Chinese Communist Party, was a new kind of party man.

I was surprised and delighted. He was the first Communist Party cadre I'd ever met who understood that he might make a better impression on a foreign writer by being hospitable than by treating her like a criminal or a spy. Had he been on some new Party PR course, I wondered?

When I explained to him that I was a food-writer and researcher interested in Sichuan pepper, his plump, generous face lit up. 'Welcome, welcome!' he said, and immediately disappeared into an adjacent office, re-emerging moments later with a glossy, full-colour calendar celebrating Qingxi tribute pepper. Proudly, he pointed out its features: the poems, the account of Qingxi's 1346-year history as a county seat, the close-up photographs of the famous wa wa jiao. 'Look,' he said, pointing, 'Can you see the "babies", the wa wa? That's the sign of authenticity.' He was keen, he told me, to spread the word about Qingxi and its pepper to the outside world.

I asked the Party's Secretary's advice about buying Qingxi pepper. 'I've heard that it's not always genuine,' I told him, 'And that some dealers import pepper from other places, and pass it off as the real thing.'

Half an hour later, he was back with two paper bags, proudly emblazoned with a printed history of Qingxi tribute pepper. The Secretary seized a bag and we smelled the pepper, which was wonderful. The skin of the peppercorns was dark pink and pimply; inside they were silky white. 'Do please show me the wa wa,' I said. He looked closely at one pair of peppercorns, then another, and another. Then he shouted in rage. 'This is not real wa wa jiao! You see, some of them have the wa wa, but others don't, they must have mixed them up, diluted them!' He was fuming. The Mayor was summoned again. 'Look, this is no good, go again, don't ask in the shops, go and find some peasant who has kept by a small supply of the best stuff. There must be some around.' (No wonder it was hard to find the real thing, if even the mayor of Qingxi was fobbed off with fake tribute pepper. I tried not to smile.)

'No problem,' he said, and stabbed out a number on his mobile phone. Minutes later someone else came into the room. He turned out to be the Mayor. 'Look here,' the Party Secretary said to the Mayor, 'Can you get a jin or so of Qingxi Tribute pepper for Miss Fu? Make sure it's good stuff.' The Mayor rushed off on his errand.

After a while a number of rather smartly dressed adults entered the courtyard. The bad boys melted away with their cards and cigarettes. The adults stood awkwardly around, looked at us for a bit, and then left. I guessed that they were government officials, but they left Mu Ma and me alone.

'Yes yes,' said the Secretary. 'But please won't you join us for dinner a little later on?' So he gave me his phone number and we arranged a time and a place.

Eventually the Mayor returned with an unlabelled plastic bag of pepper. The peppercorns were still attached to tiny fragments of twig. Their scent was overwhelming, it flooded the room. So we scrutinised the peppercorns, and indeed they all came with their wa was. Everyone was happy. 'Thank you so much,' I said. 'And now perhaps I will go and look around the temple.'

Back at the temple, I met up again with Mu Ma. In the main gateway a small band of naughty boys were sitting around a table, gambling and smoking cigarettes. The ringleader appeared to be about eleven, and was puffing away on his cigarette like an old roué, dealing cards and shuffling piles of bank notes. The others all looked wildly delinquent as they shouted and laughed, and chucked their cards and cash about the table. The ancient temple custodian looked on, quiet and resigned.

Since our last visit the main temple hall had been opened up and gaudily restored. A huge statue of Confucius in bright, primary-school colours loomed overhead. Outside, the crumbling stele and stone incense burner stood as they had for centuries. The elderly custodian of the temple pointed out the chicken feathers that were stuck to the side of the stele in a clotted, bloody mess. 'Students,' he said, 'killing chickens as sacrifices to Confucius before their exams.'

It took five strong men to manhandle the struggling pig into the yard, and pin it down on the slaughter bench, where it shrieked and wailed like a stricken human. Then the butcher plunged his knife deep into its throat, and the blood gushed out in a torrent of purplish red. The pig continued to scream and writhe for what seemed like ages. Finally, it was dead, and the courtyard ran crimson with blood. The butcher made a cut in its hind leg, and poked in the nozzle of a bicycle pump. Then he stepped on the pump, and the pig plumped up ('Easier to butcher,' he said).

It was la yue, the month of winter sacrifices. Almost every household had been rearing a pig in preparation for the New Year, and now it was time for the killing. By the roadside, fires burned under communal stoves. Steam rose from huge basins of simmering water. We watched a man rounding up his family's pig in the courtyard of his house in the centre of town. The animal grunted, bristly with apprehension. Inside, the butcher was waiting, with his sharp willow-leaf knife.

Mu Ma was busy taking notes as dinnertime approached. I reminded him that we were supposed to be meeting the Party Secretary before six. 'I'll join you later,' he said. So I left on my own. I hitched a lift on the back of a young bloke's motorbike, and almost flew down the hill, wind flicking through my hair, gazing at a sun-drenched landscape of peppered slopes and mountains salty with snow.

One man sliced off the pig's head with a large knife, and then they hung the decapitated carcass from a wooden frame. They carved it up, there in the yard, ready for salting. A woman with wet hands unravelled yards of looping intestines on the bench while a little boy ran around with a pair of trotters dangling from a piece of string. Inside the house, the women were salting chunks of fatty meat and packing them into waist-high clay jars. A few days later, they would cook them in lard, and lay them down in jars for the rest of the year.

The strong men hauled the great flabby beast on to the stove bench, where they dipped each part of its body in turn into the basinful of steaming water. Another man stoked the fire underneath with pieces of wood. The pig's face, pale and lifeless, stared out at strange angles as they manipulated it on the bench. The blanched body parts were scraped clean of hair. The men were quiet and earnest as they went about their work.

In the Mountain Villa restaurant, all the Party and government officials of Qingxi were assembled around a large, circular table in a private room. I recognised among them the smartly dressed people I had seen earlier in the temple. (So I had been right.) The Party Secretary was warmly welcoming, and raised repeated toasts to my health. 'Welcome to Sichuan! Welcome to Hanyuan. Even more welcome to Qingxi!' he cried. One or two other officials made attempts to be friendly, but it was clear that the rest of them harboured some lingering doubts about my presence. They glanced uneasily at my notebook as I scribbled. Although I listed the names of the dishes we ate in Chinese characters, my copious notes were in English, so they couldn't tell for sure if I was writing about more than just the food.

'Well, thank you,' I told him, 'I am honoured.'

'Actually this is the first time the Qingxi government has received a foreign visitor,' said the Mayor, at my side, a little abashed. (Even the famous Rose, it seemed, had not yet dined with him and his colleagues.)

The dinner was scrumptious, Sichuanese rustic cooking at its best. We began with slices of wind-dried sausage, tingly with Sichuan pepper and chilli, and chunks of delicious corn-fed chicken dressed in chilli oil. There was jia sha rou (slices of fat belly pork with glutinous rice and sweet red-bean paste, turned out of a steaming bowl and sprinkled with sugar); tea-fragrant salted greens stir-fried with minced pork; a whole pork knuckle, dressed in a lavish fish-fragrant sauce and sliding lazily off the bone; stewed brown beans with Sichuan pepper oil; a magnificent chicken stew with tian ma, an expensive medicinal tuber; and a slow, hearty stew of beef with carrot. The ingredients were locally produced and they tasted stupendous. It was the best Chinese meal I'd had in months, better than anything I'd had in the glamorous restaurants of Shanghai, and I couldn't stop eating. Rosy with wine and exhilarated with pleasure, I too proposed a toast: 'May the outside world understand and adore your Qingxi hua jiao!' The officials were delighted, and raised their cups in unison.

Mu Ma wandered in when the meal was almost finished, rudely, I thought, but I didn't say anything. We all rose from our seats, and Mu Ma used my camera to take a picture of me standing at the centre of two rows of officials, smiling, with the pepper trees and the mountains in the background. A local law officer offered us a ride back to our hotel in his police jeep, and the Party Secretary invited me to join him later at the bar of his own hotel, for drinks and karaoke. We parted on friendly terms.

Mu Ma was still hungry, so we had to find a place to eat. But he was behaving strangely: he wouldn't look me in the face and would barely speak to me. 'What's going on?' I asked, eventually. He wouldn't say. But when I pressed him, all his fears flooded out. 'What are you doing, accepting the hospitality of these local officials? You think they are generous, but I bet as far as local people are concerned, everything they give you, all that meat, all that wine, all that precious pepper, is paid for with money that they have screwed out of the peasants. I suspect they are just using you, trying to win you over. How can the local people see these officials as anything other than blood-suckers, greedy and idle? Look at them, running hotels and karaoke bars, hosting dinner parties at public expense. You've seen how poor people are here. When you said, at the pig slaughter, that you were going for dinner at the Mountain Villa, the family we were with all exchanged meaningful looks. And after you'd gone, they told me that's the place where the officials go, where they spend public money on food and drink. They hate the officials, and now they think you are one of them. As far as they are concerned, you have been eating and drinking at the expense of all the poor peasants of Qingxi.'

I was upset by Mu Ma's outburst, but angry too, and defensive. 'What was I supposed to do?' I asked him. 'I'm not like you, able to blend into the background. I'm a foreigner, I'm totally conspicuous. People in these remote places treat me like a visiting dignitary -- or a spy. What do you expect me to do when the local party secretary orders me into his office? Cause a scene by resisting? Anyway, I'm a writer, I have to see all sides of Chinese society. I want to know how things work here.' There was truth in my excuses, but I knew perfectly well that I had revelled in that dinner. Corruption and poverty had been the last things on my mind as I sipped my soup and let the steamed pork belly melt in my mouth. Grumbling, Mu Ma accepted that it was different for a foreigner. 'But I still think you should avoid these people.'

His words hit me like a thump in the stomach. It was true that corruption was rife all over China. Indeed, in the autumn of 2004, Hanyuan County itself had hit the international headlines. Venal local officials tried to evict tens of thousands of local farmers from their land to make way for a hydroelectric dam, and then to cheat them out of their compensation funds. The outraged peasants rose up against them, staging a sit-in by the dam construction site, just a few miles upriver from Qingxi. The central government, nervous at any sign of unrest, sent in top-ranking officials to reassure the populace, and paramilitary police to crush the riots before they spread. There were days of rioting, with mass attacks on government offices. Farmers were shot and killed: no one knew how many, because of the news blackout imposed on the whole county. Reading about this, I'd remembered about that paranoid policeman I'd met in 2001, and his vigilance had made more sense.

He didn't need to mention the riots of 2004. Had any of the officials I'd met been involved in the forced evictions, the compensation scam, and the violence? The Party Secretary had seemed genuinely warm and friendly, and had only recently been assigned to this job, perhaps in an attempt to clear the bad air after the riots. He certainly hadn't been around at the time. And the centre of the troubles had been a few miles away. But less than three years ago, this whole county had been under paramilitary control. After the turmoil, one local man, charged with killing a policeman, was secretly executed before he could appeal. The people of Hanyuan county, if not Qingxi itself, had even more reason to hate their local leaders than most Chinese peasants. A century after the pepper farmers had won their battle over tribute tax, some of them were again struggling to protect their livelihoods from the extortions of their leaders. And I realised that I had been so absorbed in the food that I'd forgotten all about it.

A week after leaving Hanyuan, I was woken abruptly in the vagueness of the night by a bad dream involving a pig.

The next morning, we woke early, and packed our things to return to Chengdu. The pepper in my bag had scented all my clothes, and the room. We walked to the bus station in a haze of its aroma, as the roosters were crowing, and the street vendors kneading dough for their morning buns. The first ramshackle bus to Ya'an was just leaving. 'Are you Miss Rose?' asked the conductor, as I bought my ticket.

We stopped at a small restaurant where Mu Ma dined simply on beancurd, vegetables and rice, exchanging friendly banter with the owners in Sichuan dialect. My belly felt uncomfortably full of chicken, pork, and beef. I was torn between gratitude at the kindness of the Party Secretary, whom I'd instinctively liked, and a feeling of guilt provoked by Mu Ma's words. In the end I called the Party Secretary and told him that I was tired and wouldn't make it to his karaoke bar.

Then I woke up.

I was taking care of the pig. It was enclosed in a sty at one side of an outhouse with high ceilings and whitewashed walls. One day I came in to tend to it and discovered it at the far side of the room. This was alarming, as it was supposedly penned in, and I realised it must have leapt over the wall of its sty. Then I climbed on to a thin ledge because I needed to reach something. It was a precarious position, but I clung to a little cupboard attached high up on the wall to help me balance. But then the pig reared up on its hind legs and tried to attack me, snarling and snapping. Dark, hairy, and vicious, it leapt into the air like a dog. I seized a thin bamboo cane and hit it in the face several times, but it was strong, and the cane was flimsy. Slowly the cupboard started coming off the wall, and I became desperate, knowing that I couldn't hold myself up for much longer, thrashing at the pig.

And I wondered, was I dreaming of the pig at all?