Thomasina Miers and Guy Grieve are discussing the high and low points of their foraging tour across Britain, living outdoors hunting food for survival and cooking it for epicurean delight. Grieve mistily recalls bagging a hind in northwest Scotland. “Perfect slow food; it took a day to stalk and shoot,” he says. “It was the most memorable meal of the experience, tenderloin steaks and potatoes and hawthornberry syrup.” Miers shudders at her personal nadir: “I had to spend four hours cooking meat in a force12 gale. I was so cold and miserable trying to stay with this bloody venison. It was December!” Such sweeping contrasts, but it turns out that they’re both remembering the same day.

On paper, sending Miers and Grieve on a seven-week survival trek, living under canvas, living off the land, existing like paupers but trying to eat like lords, seems a recipe for serious bickering. But safely back from their journey, Grieve, the six-foot-something outdoorsman, and Miers, the elegant chef, sit together in the civilised environs of a Soho publishing house giggling like schoolkids. The trip was Miers’s idea; the Body&Soul cook first came to prominence when, while working as a freelance food writer, she beat more than 4,000 contestants to win the BBC’s Masterchef title in 2005. For the competition she had used recipes that she had picked up during her travels in Mexico and South America. She thought up this latest culinary trek last year when she was asked by a television production company to propose her dream programme: “I love British food, so I said that I wanted to journey around Britain looking for it.”

Delicious concept, but where’s that TV-friendly sense of jeopardy? To make things much more challenging, the production company turned the food finding into a foraging expedition and recruited Grieve, a marketing man-turned-hardy-adventurer, to accompany her. The Scotsman, 33, had recently returned from a year spent struggling to survive in a self-built wilderness log cabin, a perilous expedition he recorded in his book, Call of the Wild: My Escape to Alaska (Hodder & Stoughton, £16.99). “We were both equally sceptical of each other at the start,” says Miers, 31. “But we got on very well.” Grieve nods: “That was lucky because I’d decided that if she was some kind of precious media type, I’d refuse to do it.”

Their travels did not get off to an ideal start. The journey began in Cornwall, but the weather was atrocious, and their attempts to find seafood a failure. “We did not get any fish for the first day-and-a-half,” says Miers. “Instead we found mushrooms and sorrel. We feasted on those. Actually, it was really fun. Some of the recipes I used on the trip, such as mushrooms and sorrel, are old French classic ones.” Gallic cuisine hadn’t featured highly on Grieve’s original priorities for the trip. For him, protein is fuel, preferably cooked hard to kill off all possible pathogens, rather than served daintily rare or any fancy stuff like that. “I’m not a foodie,” he says. “I have lived very happily for long periods on meagre rations and rather despise our national obsession with food.”

Grieve, a father of two children, aged 7 and 4, has a different drive, one that manifests itself as a love of living outdoors in the most comfortable and skilled way possible. His desire was to provide four-star ingredients, accommodation and kitchen facilities for Miers to create her dishes. “My hunger is to discover another way of independence,” he says. “I fish and hunt and gather for the pot because it brings me back to the perfect time of my life, when I was a child. It also enables me to feel free – free to gather food from the place where it has grown or lived. It’s also about having empathy with the animals I eat. I would not want to be hauled off to an abattoir and killed with loads of other animals in a pen. I would want to live wild and be knocked off swiftly and cleanly.

“This nation is full of food. There are 300,000 red deer in Scotland, millions of berries and nuts. Pigeons everywhere. In Cornwall, there’s seafood, in Wales mushrooms. On the trip we went where the food could be found; we followed the ingredients. Many people think that the countryside is ‘out there’ somewhere and they don’t feel linked to it. But the countryside feeds the cities and it is vital we realise that, instead of building over it.”

“We feasted and ate like kings”

As the journey progressed, the pair’s skills gelled and the larder became better stocked, with goodies ranging from rabbit, beetroot, pheasant and rosemary to crabs, chestnuts and thyme. Miers became busy developing an outdoor menu and an alfresco cookery style a world beyond the trad Brit campers’ fare of burnt sausage and beans: there was duck confit, pan-fried eels with rosemary, hare ragout, grouse pâté and even spiced squirrel popcorn. Her adaptability is the result of long experience; she started cooking at 7 and catered for friends’ parties for pocket money in her teens. “We ate like kings,” says Miers. “The film crew bought unappetising food from nearby shops while we feasted. The whole journey was great for reconnecting with the proper experience of sourcing food and eating it. Guy taught me huge amounts in terms of looking around, using my eyes. I can’t describe how food obtained like that makes you smile.”

“It was such a pleasure to just be”

Grieve, meanwhile, built palaces from canvas. “Too often, people use the outdoors as some kind of macho testing ground. The result is off-putting, uncomfortable and sometimes hazardous,” he says. “I associate camping with comfort, deep relaxation and escape from the petty concerns of modern life.” Using nearby woods for construction materials, he created campsites with capacious tents, big enough to walk around in, complete with their own internal stoves. “I worship fire,” says Grieve. But the fires that Miers desired stretched his outdoorsman skills into the Smeg league. “She made me turn my fires into top-level stoves so she could fry that, roast that, simmer that,” he says with mock woe. “If Mark Twain or Henry Thoreau had seen our tent they could have happily come in and made a cup of tea. There was nothing there that wasn’t around in their day.” Fortunately for home cooks, the recipes in The Wild Gourmets book have been formatted for kitchen and barbecue cooking.

Miers certainly appreciated the accommodation. “I woke once and it was light, so I got up – because we were going to bed when it was dark and rising at dawn. But it wasn’t morning. It was the moon, bright enough to light up this tent and make the frosty field look magical,” she says. “I realise that I need trees and greenery every so often. I work very hard and never take holidays. For me to be outside like that, it took me a long time to unwind, but it was such a pleasure to just be.”

For Miers, the end of the journey means returning to the hot stoves at Wahaca, her new Mexican restaurant in Covent Garden, newly inspired by sources of food for the pot. There will be more writing, too: her first book, Soup Kitchen, a collection of 100 original soup recipes from the likes of Jamie Oliver, Gordon Ramsay, Hester Blumenthal and Prue Leith, sold out its first print run and the profits went to homeless people. Her second, Cook, was published last year. For Grieve, there’s a whole new adventure looming, buying a boat in South America and sailing it back to Britain with his family on board. But meanwhile, there’s the British autumn and the culmination of the year’s bounties. “The seasons give us the most perfect time-table,” he says. “I’ve trained up a new dog that can flush pheasants. I’ve been watching the birds and I know where they should be hiding.”

The Wild Gourmets starts on Tuesday, Channel 4, 8.30pm. The book of the series, The Wild Gourmets (Bloomsbury, £20), is available from Times BooksFirst for £18, free p&p: 0870 1608080; timesonline.co.uk/booksfirstbuy

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