Every day is a school day with Nisha Katona, who is animatedly talking about the reasons why vegetable-focused dishes are so prominent in Indian cookery. For Hindus it dates back to tribal wars thousands of years ago, she says.

"They thought, 'We need to find peaceful ways of conflict resolution, and meat gets your blood up, it's passion-inducing and hard to digest'. So they banned meat," says the Ormskirk-born chef and Mowgli Street Food founder. "Meat is something that is associated with brutality, and muscle flexing, and none of these are things that are respected within Hinduism."

For other religious groups, vegetarianism was adopted because any life - whether human or animal - was seen as sacred.

"Jainism [is a religon] where they even sweep the ground in front of them in case they tread on an insect," she continues. "I think it's gripping, you know, the anthropology of food."

Barely pausing for breath, she goes on to explain how widows were instrumental in the evolution of vegetarianism because men were traditionally barred from the kitchen, as were women who were menstruating or breastfeeding.

"You're left with this absolutely trailblazing band of people who were allowed in the kitchen, and that was widows," she says. Forbidden from eating meat because "all of that passion-giving, heat-giving food [was forbidden] - their life was seen as over when their husbands died", these women "found really clever ways of creating flavour with very natural ingredients using just vegetables".

Katona - the daughter of a Hindu Brahmin priest - who has just released her latest cookbook, Meat Free Mowgli, is something of a trailblazer herself.

Giving up "earning good money, and a great life" working as a child protection barrister for two decades to pursue her dream of bringing authentic Indian to the British foodie scene, she opened the first Mowgli Street Food restaurant in Liverpool in 2014.

Now, five cookbooks and 15 restaurants later (with another six in the works), the 51-year-old is a judge on BBC2's Great British Menu, a regular on This Morning, and chairs the Mowgli Trust (mowglitrust.com), which raises funds for children's charities.

Turning a side hustle into a thriving career is something more and more people are aspiring to following the pandemic. So was it nerve-wracking making the leap from gainful employment to a high-risk industry?

"We nearly lost the house," Katona says, having remortgaged the home she shares with musician husband Zoltan and daughters Tia and India to get a loan. She used this with her own savings to buy an old Chinese restaurant, which became the first Mowgli to open its doors.

"I was getting four hours sleep, because I was being a barrister during the daytime and then in the evenings I would go and physically build my own restaurant, train my chefs."

A gradual transition is what she would recommend to anyone else wanting to make a similar move: "Just make sure that other rope that you're swinging to is solid." And she's keen to encourage women to follow their dreams.

"We need to invoke and inspire... particularly female entrepreneurs who come to this stage of life where you're either empty-nesting, or you're in a job that is great, but it's not inspiring you. If I can do it, you can do it."

While thousands of pubs and eateries were forced to close during the pandemic, the Mowgli chain remained intact, which Katona puts down to the regional locations of her restaurants - all but one of which are situated outside the capital.

"Outside of London, people are dining out with a vengeance. It's incredible," she says. "They understand that you go out - even if it's in your pyjamas - you go out and you eat, because that's what keeps the lights on in your high street."

The affordability of Indian street food is another key factor, a theme that's prevalent in her latest cookbook.

"When you're cooking with vegetables, with pulses, you're talking about 50p per head," says the animal-loving chef, who has a menagerie of horses, goats and dogs at home. "And I'm not talking about small portions, I'm talking about generous portions."

Her cheap eats will never compromise on taste, however. "I want everything to be really, like, a million flavours delicious. You can do that without meat, believe it or not, just by getting clever with a couple of other ingredients like spice."

And she doesn't mean blow-your-head-off vindaloos. "Forget chilli - I'm talking about spice. About knowing how to use cumin, coriander, maybe nigella seeds... spices that will just change your life."

Packed with fragrant curries, tangy pickles, creamy dals and veggie twists on Mowgli menu favourites such as sticky paneer fingers (instead of chicken wings), the book is intended to school home cooks on the basics so they can go forth and come up with ther own flavoursome combinations.

Alongside promoting the book and running the Mowgli business, Katona is shooting Great British Menu, which means she rarely gets to bed before half one in the morning ("If my restaurants are open, I will not sleep"), but this eager entreprenueur isn't fazed by her jam-packed schedule.

"It doesn't feel like work - is that not a crazy thing to say?" she ponders. "I don't ever think of myself as stressed at all."

Firmly in the glass half-full camp, she sees food as a form of self-care, and on typically hectic day like today, the in-demand chef has got one thing on her mind.

"I've got back-to-back meetings, but I know that I've got a 45-minute break for lunch," she says. "I'm going to find somewhere really nice and eat exactly what I want. For me, there's nothing else I want in life."

Meat Free Mowgli by Nisha Katona is published by Nourish Books, priced £25. Photography Gareth Morgans. Available now.