WHEN it comes to TV chefs, there are only a few who've been chopping, frying and serving up dishes on our screens for more than 25 years - and James Martin, who started his career up the road at Chewton Glen Hotel in New Milton, is one of them.

Cookery programmes have been a mainstay since Philip Harben showed BBC viewers how to make lobster vol-au-vents back in the 1940s, but even before Jamie Oliver and Nigella Lawson shot to fame in late-Nineties, Yorkshireman Martin was already a familiar face on telly, and has been ever since.

Following his popular foodie road-trips around France and America, he's now back with a new show - James Martin's Great British Adventure on ITV - plus a cookbook of the same name (his 23rd, he says).

Now, especially as the Brexit deadline looms at the end of March, is an important time to really embrace British food, says the chef, admitting this was one of the "fundamental reasons" for wanting to do the book and series in the first place.

"I'm a farmer, and this is an amazing country we live in. There are some amazing people producing some amazing food - whether they cook it, serve it, make it, or brew it," Martin enthuses.

Like a love letter to Britain and its food, James Martin's Great British Adventure takes viewers and home cooks on a journey the entire length and breadth of the land - from the Isle of Wight for feta and halloumi and Wales for the beef and lamb, to Northern Island for langoustines and Scotland for "the best fruit in the world", along with many other gems in-between.

"It was one hell of a road trip," Martin says. "I've always wanted to travel but I spent 10 years on Saturday Kitchen in the studio. I was doing home comforts that were all based here, but I wasn't going anywhere. I wondered what it would be like, to venture out."

He did venture out - and the result is a showcase of the best of the best; from cooking with Michelin star chefs and some of Martin's personal food heroes - including Clare Smyth, Sat Bains and Michel Roux Snr ("I pulled my black book of chefs out"), to uncovering little known food producers and suppliers in rural locations.

It's these people Martin is most passionate about: "The lamb farmer working in -7°C up in Scotland, getting up at 5am in the morning, isn't doing it for a new Range Rover every year - he's doing it because he's the seventh generation of the family, and we need to keep supporting that. If nobody shouts about it and we just travel all over the world all the time, that's not good."

He's almost overflowing with stories of fascinating people and underrated produce from his exploration of the British Isles. There's the vinegar producer in the Orkneys who set up his business in his dad's garage, a breed of acorn-fed hairy pig called Mangalitsa in the New Forest - and another, Middle White, farmed on the Wales-Gloucestershire border. "It's the best pork you'll ever taste, and used to be really famous in the Thirties but now we all want pigs to look like they've done 100-metre hurdles, with no fat on them, but that's where the flavour is," says Martin.

"There are 200 Middle White sows in the world and this guy has got 100 of them - they're rarer than the king panda" - but only because we don't buy their meat. "People are creatures of habit," Martin adds.

Plus, we import a lot of meat from Europe. Whatever your stance, a departure from the EU will have some bearing on this, and the British food industry in general. "There are positive and negatives," Martin says. "Fishermen hopefully should be better off because they'll stop exporting Dover sole and langoustine. But the offset of that is that the floodgates [of import trade] will open to New Zealand and, if we don't sort out this bloody mess, it will decimate the lamb industry overnight.

"Everyone knows about Welsh lamb, but people always want cheaper and cheaper food - New Zealand can produce masses of it and we can't compete against them."

But the uncertainty of Brexit isn't the only reason it's time to take a closer look at what's made on our doorstep. British cuisine, with its modern multicultural power, is finally having its moment in the spotlight. "Thirty years ago, we were deemed as the poor cousin around the world in terms of food, but in France I met some of the greatest chefs in the world, and their attitude towards British food and British chefs is totally different. Now we're on a level playing field, if not better - they see London as the gastronomic capital."

Famed for recipes that don't overcomplicate for the sake of it, long-standing Martin fans will be be pleased to know that his latest collection stays true to that approach. "I'm still off the ethos that you should never cook anything on TV that my mum can't get north of Watford," he says. "I think chefs can go too restauranty and you'll start to lose people." And although he takes some inspiration from British classics and age-old techniques, "it's fundamentally about the place, about the ingredients, about now", he adds.

It's been a long time since Martin first did work experience, aged 14, in a London kitchen, at the Park Lane Hotel ("Getting my arse kicked") - and longevity, in a world of Instagram foodies and YouTuber cooks, is not to be sniffed at. "This book is an accumulation of 35 years of work, of knowledge, built up over the years," he says. "And that knowledge, you can't buy it and you can't Instagram it."

He's got no time for flash-in-the-pan trends either. "The health food bloody thing or vegan month, do we need a whole month for it? We spend 11 months eating what we want, then comes January... It's baloney," he says, laughing.

"Food is one of the pleasures of life, and most of us don't enjoy most things and do a job we don't like, so just eat what you want."

HOW TO MAKE JAMES MARTIN'S CARAMELISED ONION, COURGETTE AND WENSLEYDALE QUICHE

This vegetarian dish is pure comfort food.

Quiche is a British classic - but this recipe from chef James Martin shakes it up with the addition of Wensleydale (a variety from Hawes in Yorkshire), and ribbons of courgette and courgette flowers, for a dinner party dish to impress.

"'Real men eat quiche', is what the team told me as I made this. I don't know about that, but I can tell you that Wensleydale cheese is a great addition," says Martin.

Ingredients

(Serves 8)

1tbsp olive oil

15g butter

2 red onions, sliced

Sea salt and freshly ground black pepper

2 eggs

2 egg yolks

300ml double cream

100ml full-fat milk

2 small courgettes, around 225g, thinly sliced, lengthways

3 courgette flowers, sliced lengthways

175g crumbled Wensleydale cheese

For the pastry:

300g plain flour, plus a little extra for dusting

150g butter, chilled and diced

A pinch of sea salt

A few thyme sprigs, leaves picked (optional)

1 egg, beaten

Method

1. Start by caramelising the onions for the filling. Heat the oil and butter in a medium pan over a medium heat. Once the butter has melted, stir in the onions and a pinch of salt. Cover and cook over a low heat for 20-25 minutes, stirring every now and then until the onions have softened and caramelised. If they look as though they're burning, add a tablespoon of water and stir in . Spread onto a plate and set aside to cool.

2. Make the pastry. Put the flour into a bowl, add the butter, salt and thyme (if using) and rub together with your fingertips until the mixture resembles coarse breadcrumbs. Add the egg and mix with a knife until the mixture forms clumps, then bring together lightly with your hands. Add a couple of teaspoons of water if the dough feels dry. Dust a clean work surface with flour and knead lightly and quickly until smooth. Wrap in clingfilm and chill for 30 minutes. Preheat the oven to 180°C (160°C fan)/350F/gas 4.

3. Lightly flour your work surface and roll out the pastry to a rough circle measuring about 32cm in diameter. Carefully lift the pastry into a 27cm fluted tart tin and gently press into the corners.

4. To make the filling, put the eggs and egg yolks, cream and milk into a jug and whisk together. Season well and whisk again. Spread the onions over the base of the pastry, arrange the courgettes and courgette flowers on top and scatter over the cheese.

5. Pour the egg mixture into the tart tin and give it a little shake so that it spreads evenly. Carefully slide the tart tin onto a baking sheet and bake in the preheated oven for 45-50 minutes, until the filling is set.

6. Once cooked, take the quiche out of the oven, let it sit for about five minutes, then trim the pastry edges. Serve hot, warm or cold with a green salad. Leftovers keep very well for the next day but the filling will be a little firmer after a night in the fridge.

HOW TO MAKE JAMES MARTIN'S BLOWTORCHED MACKEREL WITH FENNEL AND GRAPEFRUIT SALAD

Because who doesn't want an excuse to use a blowtorch in the kitchen?

Simple but beautiful, this mackerel recipe was cooked by James Martin on the back of a fishing boat.

Mackerel is a sustainable fish from UK shores, and it's packed with omega-3 fatty acids and a wealth of essential vitamins and minerals. Pair with a salad of fresh British ingredients, like grapefruit and fennel, and it's win-win on the sustainable front.

Ingredients

(serves 2)

1tbsp caster sugar

1tsp pink peppercorns, lightly crushed

3cm piece fresh ginger, peeled and grated

A few dill sprigs, chopped

Sea salt

50ml white wine vinegar

1 pink grapefruit

1/2 medium fennel bulb, thinly sliced

Freshly ground black pepper

1tbsp olive oil

4 mackerel fillets, skin on

For the dressing:

100ml full fat creme fraiche

1cm piece fresh ginger, peeled and grated

Sea salt and freshly ground black pepper

Method

1. Put the sugar, peppercorns, ginger, dill and one teaspoon of salt into a medium bowl then stir in the vinegar.

2. On a board, slice the top and bottom off the grapefruit then carefully cut away the skin and pith from the fruit. Cut between each segment and add the flesh to the bowl, reserving all the juices and pouring these into the bowl, too. Add the fennel and any fronds to the bowl. Season with a little black pepper and toss everything together (including the dill and grated ginger).

3. Rub the oil over the mackerel and season well. Pop the fillets, skin-side up, onto a baking sheet. Using a blowtorch, scorch the skin of the mackerel until charred and the fish is cooked through. Alternatively, preheat the grill to its highest setting and cook the fish for three to four minutes.

4. To make the dressing, mix the creme fraiche and ginger together in a bowl with a little seasoning.

5. To serve, spoon some dressing onto each plate, lay two mackerel fillets on top and half of the salad alongside each.

HOW TO MAKE JAMES MARTIN'S INDIVIDUAL BEEF PIES WITH OYSTERS

The ultimate surf and turf.

"If you've never eaten the classic combination of beef and oysters, you should try it," James Martin declares.

The TV chef made this recipe in Cornwall, picking up the oysters from a family-run farm in Porthilly. "The place is perfect for oyster production, thanks to the tidal stream bringing seawater to feed and filter the oysters," Martin says in his new book, James Martin's Great British Adventure.

Ingredients

(Serves six)

3tbsp vegetable oil

2kg shin of beef, diced

Sea salt and freshly ground black pepper

2 shallots, peeled and diced

500ml beef stock

250ml British bitter

A little plain flour, for rolling out

500g ready-made puff pastry

2 egg yolks, for egg wash

For the oysters:

Large bunch of flat-leaf parsley

100g sourdough bread, roughly chopped

Zest of 1 lemon

12 just-shucked oysters in their shells

You will also need 6 x 12.5cm pie dishes

Method

1. Heat the oil in a very large, non-stick casserole pan then fry the meat, in batches, until well browned all over. Transfer each batch to a plate as you do it and season well.

2. Once all the meat has been browned, return it to the pan with the shallots and pour over the stock and beer. Cover, bring to the boil then reduce the heat and simmer gently for two hours.

3. Spoon into a large shallow dish and cool. You can make the stew up to a day in advance and chill in the fridge until you want to assemble the pies.

4. Preheat the oven to 200°C (180°C fan)/400F/gas 6. Lightly dust a clean work surface with a little flour then roll out the pastry until it is 2mm thick.

5. Using the top of one of the pie dishes as a guide, cut out six circles slightly larger than the dishes, then fill the pie dishes with stew (we used mini ovenproof saucepans).

6. Brush the edges of the pastry lids with the egg wash then turn over and lay on top of the dishes and seal around the edges. Brush the tops with egg wash, sit the pies on a large baking tray and bake for 40 minutes, until the pastry is crisp and golden.

7. While the pies are in the oven, prepare the oysters. Put the parsley and bread into a food processor and blitz to make fine breadcrumbs. Add the lemon zest and blitz again. Season well.

8. Arrange the oysters on a baking tray, spoon the crumb mixture over the top and bake on the top shelf of the oven for 10 minutes. To serve, pop the pies onto plates with two oysters per person.

n James Martin's Great British Adventure continues every weekday on ITV. The accompanying book, James Martin's Great British Adventure: A Celebration Of Great British Food With 80 Fabulous Recipes by James Martin is published by Quadrille, priced £25. Available now.