Choosing the rising stars of the restaurant world is a tricky business. The work is so arduous and the competition so damn demanding that today's promising newcomer can, all too easily, become tomorrow's flash in the butter-smeared pan. Here at OFM, though, we think we're pretty hot at spotting talent. Six years ago, when we last shone the spotlight on unknowns that we thought were destined for great things, we identified a set of chefs who have gone on to be household names or open restaurants that have set trends the rest of the restaurant world has been forced to follow.

There was Angela Hartnett who, back then, was just one of Gordon Ramsay's backroom girls, but who now has fronted her own TV shows and won a Michelin star in her own right. It's the same story with Marcus Wareing who, in 2001, was the quiet man at the stove of Petrus. Today he has two Michelin stars.

In 2001 Jason Atherton was toiling in Dubai for the Ramsay organisation. Today he is renowned as the man who came up with the concept - and the all-important grazing menus of precisely calibrated food - for Maze, a brand that is being rolled out around the world. There was John Campbell, who also went on to win his second star; Michael Caines, who has become a regular on TV; and Hywel Jones, who has won award after award.

So what of the new crop? Being picked by Observer Food Monthly guarantees nothing, of course. They're the ones who will have to do all the hard work. Interestingly, though, the restaurant world has moved on from 2001. Back then a number of our picks were deputies to other people. This lot all hold, or have held, Michelin stars in their own right.

Only one - also the only woman - is working for somebody else, though that somebody else is Gordon Ramsay and the restaurant is his flagship 44-seater on Royal Hospital Road in Chelsea. Clare Smyth, from Northern Ireland has, at the age of 29, become his head chef overseeing the most important kitchen in his empire. 'Clare has an instinctive palate and a self-determined level of focus, a tunnel vision for perfection that is very rare in any chef today - male or female,' says Ramsay of his head chef. 'A talent like Clare Smyth comes through the kitchen maybe once every 10 years.'

The other four - Tom Kitchin, Robert Thompson, James Sommerin and Tristan Mason - are as focused and self-confident a bunch as you could hope to meet. When we showed them the checked chefs' trousers we wanted them to wear for our shoot, they weren't happy. Those were the kinds of trousers worn by burger flippers, they said, and they were not burger flippers. The best that could be said, announced another, was that Gary Rhodes once wore a pair like that. And they weren't like him either. They wanted us to know that they are the new guard: the future, not the past.

And so let us place on record that these chefs are not the sort to flip burgers and they are certainly not Gary Rhodes. They are the new breed of young, eager and hungry cooks, who are willing to put on trousers they hate, if that's what it takes to make the picture work. For that - and for their blistering talent - we salute them.

1Claire Smyth, 29 Gordon Ramsay, London

Satisfied by nothing less than perfection, Smyth, at just 29, has landed one of the industry's most desirable jobs, head chef at Gordon Ramsay's flagship restaurant.

2 Robert Thompson, 25 Waldo's, Cliveden House, Berks

Few chefs have had as blistering a start as Thompson. At 19 he joined the famed Michelin two-star restaurant Winteringham Fields in North Lincolnshire. At 22 he was installed as its head chef by chef de cuisine and owner Germain Schwab. 'It took about a month for the scale of the responsibility to strike home,' he says. 'But Germain was there to guide me.' Schwab, he says, has been a huge influence. 'He was always interested in flavour first and that's what I take from him.'

When the Schwabs sold up Thompson stayed on as head chef and, though Winteringham lost one of its stars, Thompson regards the one that remained as his, no mean feat for a man still in his early 20s. A few weeks ago he returned to the Thames Valley, where he grew up and went to college, to take over the kitchen at Cliveden, the grandest of stately-home hotels. For now his ambitions are simple. 'I want to win back my first star and then go for two,' he says. 'I want to build my reputation, not on TV, but solely for my food.' When asked to name his signature dish he was modest. 'I'm only 25 so it's going to take a while for that to emerge. But if you asked me to choose it would have to be a hare royale that I learnt from Germain. It's unembarrassed in its luxuriousness.' As is so much of his cooking.

Signature dish: Hare royale, with rosti, hare sauce and foie gras

Mentor: Germain Schwab

What they say: 'Do not shy from the six-course gourmet menu or the à la carte because it is at the top end that Thompson soars, sending out extraordinary dishes that are deeply complex.' Good Food Guide.

Cliveden, Taplow, Berks, 01628 668561, clivedenhouse.co.uk

3 Tom Kitchin, 30 The Kitchin, Leith, Edinburgh

Tom Kitchin is not afraid of hard work if he thinks it will benefit his career. After years working at a senior level with the great Pierre Koffman at La Tante Claire in London, as well as with Guy Savoy in Paris, Kitchin took a job with Alain Ducasse in Monte Carlo. And it was like starting all over again. After having risen to be a senior sous chef, all of a sudden he was back to third commis, the lowliest of the low. 'I was willing to swallow my pride,' he says now, 'because I knew it was the right thing to do.'

The decision paid off. Today he has his own restaurant back in his native Scotland where, earlier this year at the age of 29, he became the youngest-ever Scottish chef to win a Michelin star. His food, he says, has been defined by his experience with Koffman. 'He's still my mentor. In fact all the plates, cutlery and glassware are from La Tante Claire,' he says. 'What really matters with Pierre, though, is his food. There's no ponciness. It's all about flavour and that's what I try to concentrate on too.' What's important, he says, is to focus on simplicity and the seasons, not necessarily on luxury ingredients. 'That's something else I learnt from Pierre.' It seems to be working. Weekend tables in the restaurant that he runs with his wife Michaela - she handles the front of house - are now booked out six weeks in advance and all the other services are fully booked too. That's how he likes it. Indeed, ask him about his ambitions and he doesn't talk about stars or accolades. He says, 'I want my restaurant fully booked for lunch and dinner every day. There's no better buzz.'

Signature dish: Boned and rolled pig's head, roasted langoustine tails and a crispy pig's-ear salad

Mentor: Pierre Koffman

What they say: The pig's head dish is 'an extraordinary combination and not one for the faint-hearted... there's no denying the technical brilliance.' Daily Telegraph

The Kitchin, Leith, Edinburgh, 0131 555 1755, thekitchin.com

4 James Sommerin, 29 The Crown, Whitebrook, Wales

James Sommerin's achievements are all the more impressive because, unlike our other rising stars, he cannot claim the tutelage of one of the greats of modern gastronomy like Germain Schwab or Pierre Koffman. He cites the influence of one Richard Lyth, head chef at the little known Farleyer House Hotel in Scotland, where he undertook almost all his training. 'He taught me everything, cooking methods, butchery, the lot.' But James is just as likely to cite the influence of his grandmother back in Wales, and the baking they did together on Saturday mornings when he was a kid, or the pocket money job he did prepping ingredients in an Italian restaurant.

In his early 20s James moved back to Wales and the Crown at Whitebrook. He became head chef in 2003 and this year won his first Michelin star. 'That was mind-blowing,' he says. 'I really wasn't expecting it.' He was simply concentrating on his food. 'Gordon Ramsay's a big influence on me because of his pure passion, and I'm interested in the new wave of cookery though I think a lot of it gets out of control,' he says. 'My food has a French influence. It's not obscure, but it is modern. When I cook I try to keep honest. I don't like to overshadow the ingredients.' And Wales, he says, is a great place for that. 'We've got some of the best game, lamb and beef.' Which is why he's determined to stay there. For James achieving his ambition - another star - does not mean moving away. 'I want to be the first Michelin two-star in Wales,' he says.

Signature dish: Lamb three ways: 24-hour cooked shoulder, roast loin, sweetbreads with truffled pommes puree

Mentor: Richard Lyth, Farleyer House Hotel, Scotland

What they say: 'The matter-of-fact menu description of my starter - "salad of new potatoes, wild mushrooms and truffle" - didn't do justice to a dish that was far more than the sum of its parts ... perfection.' Guardian

The Crown at Whitebrook, nr Monmouth, 01600 860254, crownatwhitebrook.co.uk

5 Tristan Mason, 31 The Orrery, London

Talk to Tristan Mason and you might assume he had chosen a life in the kitchen while still in his pram. He oozes certainty and commitment, and a rare intensity about his food which seems to come from deep within. Not so. 'I was doing a graphic-design course when I caught the bug,' he says. 'I was washing pots at Brocket Hall and that's what got me interested in cooking.' It is, he says, another way to channel his creativity, which he has in abundance. Mason cooked at the Mirabelle, learning the classics, and describes Marco Pierre White, who then owned the restaurant, as a big influence. 'He was the chef everybody wanted to be.'

That was followed by a stint at the Greenhouse under Paul Merritt who, he says, taught him to loosen up after all that time cooking Mirabelle classics. Finally he went to a pub called the Hare in Hungerford where, aged 29 and with just one other cook in the kitchen, he achieved his first Michelin star. He calls his food 'eclectic modern French', which is as good a title as any for dishes like cider-marinated salmon with crispy pork belly and grain-mustard ice cream, or roast teal with confit duck, red-cabbage puree and caramelised chestnuts.

This year, he brought that food back into London, when he took over as head chef at the Orrery, generally regarded as the star in what was until recently the Conran Restaurant Group. He has big shoes to fill. The Orrery was where major names like Chris Galvin and Andre Garrett made their reputations. Mason accepts it's a big job. 'It's a serious jump but I wanted to get back into London,' he says. 'There are 12 cooks in the kitchen, but I've got complete autonomy. Of course you've got to cook for the clientele but you've also got to move it forward.' No one should doubt his ability to do just that.

Signature dish: Lobster with roast root vegetables and beef consommé

Mentor: Paul Merritt

What they say: 'Mason's food has the sophistication of someone in tune with handling quality ingredients to produce excitingly original dishes.' BBC Food website.

The Orrery, London W1, 020 7616 8000, orreryrestaurant.co.uk

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