When Nisha Katona was growing up in 1970s Lancashire, part of the only Asian family in the village, food was never just food. To her Indian immigrant parents, cooking large pots of curry and inviting the neighbours in was an “olive branch”; a way of connecting with a community in an environment where they were frequently “firebombed and spat at”.

For Katona and her brother, however, it was more complicated. “We were really ashamed of Indian food,” she says. “Embarrassed by how it smelled. It represented everything that made us different. We would beg our parents not to cook it when our friends came over.”

Half a century later, the very cuisine she once shunned has become Katona’s life’s work. Today, she is the founder of Mowgli Street Food, the Indian restaurant group serving 40,000 diners a week across 26 UK restaurants, many of them with queues around the block. She is also the author of seven cookbooks, the latest of which, The Curry Bible, brings together more than 100 “greatest hits” recipes and is the kind of book which might become the sort of well-thumbed kitchen staple that sits on the shelf for years, splattered with turmeric and oil, and passed between generations.

“It feels almost narcissistic, doesn’t it – writing a book called The Curry Bible?” she says, laughing. “How utterly ambitious. But there is something about curries that this country loves – for all the street food recipes I share, it is the classics people always want to know about.”