Sharing lunch with Fuchsia Dunlop we savour smacked cucumbers doused in sesame sauce, thinly sliced pork wrapped around carrot shreds, a glossy bowl of fish-fragrant aubergine and dry fried beans from the wok, laced with pickled veg and minced pork.

When she wrote the original edition of her first cookbook, The Food of Sichuan, dishes like these were almost unknown in Britain and the States, let alone eaten in restaurants ("You couldn't buy real Sichuan pepper!").

Almost 20 years on, the cuisine "has become wildly popular" says food writer Dunlop, who throughout the intervening years has continued travelling around the region, magpie-ing recipes and interviewing chefs – and as a way to "keep up the eating".

At 11, Dunlop – who grew up in Oxford – told a teacher she planned to be a chef and, after graduating from Cambridge University, became particularly interested in China through a BBC sub-editing job.

Signing up for evening classes in Chinese (she eventually learned to speak the language fluently), she later won a British Council scholarship for a year of postgraduate study in China.

"China 20-25 years ago was another world," she recalls. "I was supposed to be studying other stuff, but the food was just captivating, and the city was full of these small streets with little restaurants and snack sellers and markets. It was all just more exciting and varied, fresher, more delicious, than any Chinese food I'd ever had before."

She began recording everything in her diaries "without any plan" and then leapt, becoming the first westerner – and one of very few women – to train at the Sichuan Institute of Higher Cuisine in Chengdu. "They would never have imagined this strange young woman who wanted to learn cooking would have gone on to this," she says, bemused.

Since then the country and cuisine have developed considerably, but then, "Sichuan food has always been very open-minded and incorporates lots of different influences," notes Dunlop.

"One of the most extraordinary things is okra, it was really unknown just a couple of years ago, but now it's on every restaurant menu," she buzzes, while there's also a craze for an 'ice plant' – "a sort of succulent, eaten raw. It has green leaves, but it looks like there's ice all over them, so when you eat it, it really crunches noisily in your mouth."

You can now get pizza and localised French patisserie too. "It's constantly evolving," says Dunlop, although in terms of architecture that's not always a good thing.

"When I lived in Chengdu there were whole neighbourhoods of houses made of wooden bamboo, traditional Chinese medicine shops with all the herbs in drawers, and it was a street life in some ways that hadn't changed for hundreds of years. [That] was very enchanting for a foreigner," she remembers. "This has all been demolished, I miss that most of all."

If Sichuan is entirely new to you though, Dunlop is the ideal guide, with the updated version of The Food of Sichuan reflecting how the region and its tastes have changed, as well as encompassing its core tenets.

"People [often] think Sichuanese cooking is all about fire and spice, chillies and lip-numbing Sichuan pepper, and actually it's not," she muses, explaining how the Chinese word for Sichuan pepper is the same as 'pins and needles', or anaesthesia. "It's all about variety."

"Good Chinese and Sichuan food is all about balance, not about battering your palate with lots of heat and nothing else," she adds.

The worst misconception around Chinese food in the western world – largely based on lurid, deep-fried Friday night takeaways – she says, is that it's bad for you. "I think the Chinese know more about healthy eating than anyone else," she explains. "Food in China has always been intimately related to medicine, and people use food to treat illness and indisposition, and the way people eat in an everyday way at home is a lot healthier than the way many people eat in this country."

For instance, meat is used sparingly: One western portion of meat would be cut into slivers and stir fried with vegetables, then served with more vegetables and rice. "It's a really good model of healthy and sustainable eating, when it's done well."

The vegetable aspect is arguably what she loves most about Chinese cookery. "The Chinese are brilliant at making vegetables taste exciting," says Dunlop, pointing to the dish of smacked cucumbers. "Cucumber, on its own, not very interesting, but put it with a Chinese dressing and it's really interesting."

Chinese food has the power to redefine what it is you find delicious too. "Years of Chinese food has completely changed my palate," says Dunlop, explaining how the biggest barrier in getting to grips with the cuisine can be texture foods, "because in China, and particularly in Sichuan, people like eating a lot of ingredients that have rubbery, slithery, gristly, crunchy textures, that westerners, in general, actively dislike. Things like gristle in a chicken's leg, and jellyfish and goose intestines."

For a long time she says, she would politely eat these things, "but they didn't give me any pleasure," and then at some point she realised she'd begun to enjoy them. Learning to savour mouthfeel and texture "massively expands your appreciation of food in general" says Dunlop, because it opens up "a wider range of sensations".

So, if you are planning a trip, or are just beginning to explore Sichuan cuisine, she suggest you "try to open your mind to the idea that texture is an important part of gastronomic pleasure. China is a really food-focused culture, go with a certain humility. There is a lot to learn from it."

Dunlop calls her own fascination with Chinese cuisine a "lifelong project". "To be transmitting things into people's kitchens," she adds, "is very moving."

l The Food of Sichuan by Fuchsia Dunlop is published by Bloomsbury, priced £30.