Her recent broadside at book critics who give away plot twists corroborates this fierce reputation, and there are even tell-tale signs on the list of "little known facts" on her website.

Fact 18, for example: "I once met Ewan McGregor at a party, thought he was an ex-pupil of mine and lectured him (at some length) about letting his French get out of practice."

And fact 44: "I'm incapable of hiding my feelings when I'm around someone I don't like."

So it is a surprise to see a smiling woman with a soft, striking face and a not-quite-Yorkshire accent, sitting in a hotel lobby in a big woolly jumper. Harris, it turns out, is quirky and loquacious and not at all a battle?axe, though one imagines she could be very formidable if need be.

Since 1999, when everyone in the world seemed either to be reading Chocolat, Harris's third, Whitbread Prize-shortlisted novel, or watching the Hollywood adaptation starring Johnny Depp and Juliette Binoche, she has written ?many more books, every one of them a bestseller including two sequels to Chocolat, cookbooks and a separate series spawned by her love of Norse legend. Now comes her second book of short stories, A Cat, a Hat, and a Piece of String, a moreish collection that is variously comical, scary, sad and surreal?.

Several of the stories feature ghostly goings on, including a creepy tale about a man's obsession with a house. "I live in that house. It's old, it creaks and we're always finding its little secrets. We found these little pair of baby shoes in the chimney. I don't feel afraid in it but it's definitely slightly alive. We often make jokes about the pantry ghost. I'm not sure I believe in the whole 'ghost-afterlife' thing but I think places are marked by people who have been there. There is also a big white dog in the garden. Several people have seen it. A ghost dog."

Another short story, "Cookie", exemplifies what Harris does best: she incorporates food deliciously into the emotional dramas of her characters. She is so celebrated for it – several books after Chocolat revolved around feasting and food, including Blackberry Wine and Five Quarters of the Orange – that fans have been sending her cake and chocolate ever since and her cookbooks were written after repeated requests for recipes.

Writing about food, she says, has always been cathartic, though "Cookie" reminds us that there's a dark side to it, too. "I am fascinated by how people eat and what it reveals about them. 'Cookie' was one of those stories I wrote while I was going through a phase when I just wanted to binge eat. At one point, I went on this radical diet and lost four and a half stone. It was an 'eat nothing but packets of chemicals' diet. I went to a diet club where everyone had a story."

In the third and latest Chocolat sequel, Peaches for Monsieur le Cure, food appears at its most politicised. The fictional village of Lansquenet is now also home to Moroccan Muslims and there are mouth-watering descriptions of indigenous cuisine. There was some rumpus over the fact that Harris? took on such freighted topics as immigrant communities in France and the Islamic niqab but there were no complaints from the Muslims who read it. In fact, they sent letters saying they loved the descriptions of food and that they recognised their grandmothers.

Still, she admits she was initially apprehensive about writing about a community that was far removed from hers.

"I was terrified of someone saying 'how dare you, a white person, write about us'. Then I thought, 'sod it, it's a story'. The worst thing would have been to say I can't write a story about those people. And I live in Huddersfield [which has a large Muslim community] for heaven's sake."

Her interest in the niqab was piqued years before its banning across Europe a few years ago. "I had written so many stories about identity in different ways that it seemed the perfect continuation of this theme. I was genuinely curious about why people wore it and I got friendly with the headmistress of my local Muslim girl's school in Huddersfield."

This was not the first time she had come into close contact with young Asian girls. She worked in a comprehensive school in Dewsbury, more than a decade before the connection between the Leeds town and the ?July 7 London bombers was made. Back then, she said, certain problems were apparent. "There were not exactly forced marriages but every year, some girls disappeared from school and nobody knew where they went and they didn't exactly want to go." By contrast to the large Asian community there, Barnsley was mono-cultural when she was growing up. "There was one non-white boy in our school. He was from Nigeria. It was not so much racism, but everyone was curious about him. He was called Toby and I remember at one point, people paying him money so that they could pat his head because he had bouncy hair. Living in close-knit, white isolationist communities does do something to you. There's often a faction of people that says 'you're an outsider. You don't belong.' "

So what must it have been like for her mother, a glamorous French woman who emigrated after marrying her Yorkshire father?

"My mother was quite unusual in Barnsley but she is incapable of being traumatised by anybody. I expect all the traumatising was done by her. She was a teacher, working at the same school as my father. Apparently she went in on her first day and she said 'I have tried very hard to learn your language. Now you will learn mine.' "

Barnsley, she adds, isn't much more multicultural even now. A lot of people from her school are still there. But then again, so is she – or a few miles away. She is married to Kevin, whom she first met at school and with whom she has a daughter, Anouchka, who recently left home to read English at London University. "I'm still there because I like it," she says, and because the grounded Yorkshire mentality was a good antidote to the disorienting effects of sudden success that followed Chocolat.

After it was published, she decided she wasn't going to write a sequel, but found herself returning to the story.

"I said I wasn't going to follow it up and I made it almost impossible. I gave it a nice ending, but then I thought 'oh, but what if I did it this way?' I have a tendency to pick up my own challenges. The more difficult something ? is, the more I want to try it."

When the film rights were bought, her fear was that the end product would not resemble the novel in the slightest.

"At first they were planning on having Whoopi Goldberg in the American ?midwest. Then it was Gwyneth Paltrow in present-day New York – as if anyone would believe she eats chocolates! When I found out that they were keeping to the plot and keeping it to France, there was overwhelming relief."

She has been plagued by questions about Chocolat, the film, ever since ("I've been asked if I snogged Johnny Depp!" she chuckles, adding "He isn't my type"). Then there is the question of the return of Vianne Rocher, the chocolate-making witch, fourth time around?

"I daren't say no. Vianne might be back if she has a story which is fundamentally different enough. What I never wanted to do was to write Chocolat 1, 2 and 3, which I why I waited between each one to find a story I really wanted to write as opposed to one the publishers would have liked me to write.

"I don't think Vianne has finished her trajectory, she is not complete in her happiness. Perhaps she never will be. She has got two daughters. I may write about them, but not yet, and I will not go looking for a story. It will find me or it won't."

The Independent