So what does the world's best chef do for Sunday lunch?

So what does the owner of the world's best restaurant do for Sunday lunch? A helicopter to Paris for brunch at the George V? Something chi-chi at J Sheekey? Or perhaps a good mouthful - and maybe even a spicy earful - at Gordon Ramsay?

The answer, for Heston Blumenthal, winner of no fewer than three Michelin stars for the Fat Duck in Bray, Berkshire, is none of the above. It's roast chicken at home with wife, Susanna, and children Jack, Jessica and Joy - plus a plateful of pudding to follow. Something, perhaps, like treacle tart or Black Forest gateau, two desserts that will feature in his new cookery show later this year.

For Blumenthal, 39, christened "Dr Strangefood" for his advocacy of the science of taste and unusual dishes such as snail porridge, the important thing about Sunday lunch is not culinary adventure, let alone fashion - it's about good old, traditional family togetherness. That's why, as he tucks into another Sunday bonding session at his three-bedroomed house in Marlow, he's decided to back the IoS Sunday Lunch Campaign.

"Foremost, it's about the company, then about the food," he said yesterday. "The key to the food is keeping it simple. It doesn't need to be an unnecessarily stressful experience at all; it should be very relaxed and pleasurable. I wouldn't bother with a starter - but I would definitely bother with a pudding."

He said this is a treasured ritual in his own home - and a practice that should be protected today in Britain, where record numbers of families fail to sit around a table together for regular meals. "Sunday lunch is not a chore, it is one of life's great treats," said Blumenthal. "I absolutely support your campaign. The world would be a far worse place if the tradition of Sunday lunch were to disappear.

"This is something we need to act to protect, to save and to cherish. As families, we all need to sit down and spend time together."

Blumenthal, who won his three Michelin stars in record time, said he looked forward to his Sunday meal as an opportunity to relax after a hectic working week in the kitchen. "My wife does all the cooking on a Sunday. That's the tradition in our house - it's the one time I get to put my feet up," said Blumenthal. "For us, it's very important to involve the kids too, and to just spend time sitting around the table together, having fun and having a laugh."

All very different from the pressures of his professional kitchen at the Fat Duck, where up to 12 people can be at work at any one time. Nor does his wife have the benefit, as he does at the restaurant, of an outhouse where jar after jar of flavour essences are stored. She still, however, cooks a mean roast chicken, says Blumenthal.

His enthusiasm for family meals is understandable. It was at a meal with his family as a teenager, in a French restaurant, that he was first entranced by gastronomy. The road he then took to professional cooking was far from a straight one. He was a trainee architect, photocopier salesman and even a debt collector before he and his wife, a former nurse, sold their house, moved in with his parents and started the restaurant in Berkshire that is now world famous.

Blumenthal splits his time between the Fat Duck - voted World's Best Restaurant by a panel of international food pundits in 2005 - and his other property, Bray's village pub, the Hinds Head. He has made his name at the Fat Duck through his innovative, and self-taught, approach to the "science of cooking" - resulting in creations such as sardine-on-toast sorbet, snail porridge and the famous egg-and-bacon ice-cream. It is not for everyone. After he won the best restaurant title, The Sun sent two readers to sample the food. The subsequent piece appeared under the headline: "Snail porridge? I'd prefer a Big Mac". But, he said, at home his family liked to keep it simple. "It's normally roast chicken on Sundays," he said. "The drink is part of the ritual too, of course. It depends on what we're eating, but I love a good sherry with my Sunday lunch. I could quite happily drink sherry throughout Sunday lunch. There's just something about a nice chilled glass of fino, because it seems to get the saliva, the juices going in your mouth. When you bite into an apple you get a similar effect - it's good to get the appetite going."

Blumenthal joins a growing list of celebrity chefs who have thrown their weight behind our campaign, including Michel Roux, Jean-Christophe Novelli, Anthony Worrall Thompson, Hugh Fearnley-Whittingstall and BBC2's latest culinary stars, the Hairy Bikers. The campaign, launched two months ago, is also supported by experts from Childline, Relate and leading hospitals.

Our campaign is much needed. As recently as a generation ago, British families sat together for a meal nearly every day. Today, however, a quarter of us don't even have a dining table. Just 29 per cent of families eat together more than once a week, and even then more than three quarters admit they spend that time watching television rather than interacting with each other.

It's a subject close to his heart - and hearth. Blumenthal, who was made an OBE for services to the hospitality industry earlier this year, said: "Once you turn the TV on, people turn off. Mindlessly stuffing food in your mouth while watching the television doesn't do anything for anyone. The process of sharing food, of communicating and interacting with each other without any other stimulation, can be so rewarding. This is the kind of thing that brings families together. It is hugely important."

What's the secret of getting the family around the table for Sunday lunch? Each month, we will publish a selection of your letters with a mouth-watering prize for the best one. Write to: Sunday Lunch Campaign, The Independent on Sunday, 191 Marsh Wall, London E14 9RS, or send an email (Subject: Sunday lunch) to: sundayletters@independent.co.uk

Recipe: Mrs Blumenthal's Sunday roast

ROAST CHICKEN; ROAST POTATOES; YORKSHIRE PUDDING; CONFIT OF CARROTS; CABBAGE BRAISED WITH SMOKED BACON AND CHILLI; GRATINATED CAULIFLOWER CHEESE, FOLLOWED BY APPLE TARTE TATIN

The Sunday meal in the Blumenthal household is typically cooked by Heston's wife, Susanna, with help from the couple's three children. "It's normally chicken with roast potatoes and vegetables," said Blumenthal, who has a son, Jack, 13, and two daughters: Jessie, 11, and Joy, eight.

"The fun thing about it is that it's a meal where you help yourselves, so we always have arguments over who's going to get the crispiest bit of the potato or the wishbone from the chicken, and that's all part of the experience.

"I'd guess that people not having Sunday lunches are the ones who don't enjoy cooking, so the first thing to do is remove that barrier. Start off with something really simple and comforting that everyone will enjoy - like roast chicken."

Pudding is a particularly important part of the Sunday meal at the Blumenthal house, with tarte tatin a regular favourite.

"We'll often have a tarte tatin for pudding, with apples, pears or even mangoes," said Blumenthal. "My 11-year-old, Jessie, is a dab hand at making this now.

"Ideally, if you have kids, involve them in the cooking process as much as you can. They'll be much more willing to sit down and eat if they feel a part of it.

"In our house, it's normally not any problem at all getting the kids to help out with the cooking - the only hard part is getting them all involved in the clearing up."