Whoever said "it is better to travel than to arrive" never went to Heathrow on a bank holiday weekend. Terminal 2 looked like a modern Hogarthian hell over Easter. Streams of sleet-flecked passengers snaked through the worn-out, lash-up-and-make-do slum, their only distraction cafés serving dehydrated sandwiches and overpriced bottled water. "It's a f****** national embarrassment," said Gordon Ramsay. For once, the language seemed appropriate.

Ramsay had just arrived home on a flight from Paris, where he had opened his first French restaurant, Le Trianon, at Versailles. Today he cooks up another high-profile first by opening the only airport-restaurant run by a Michelinstarred chef. Plane Food, in Heathrow Terminal 5, began serving English breakfasts at 6am when the first departing British Airways passengers arrived.

As the finishing touches were being applied over the weekend, the 41-year-old Scot gave the Evening Standard a preview. "F*** me," he said as he cleared security and walked in to the 175-seat restaurant in the empty terminal. "The last time I was here, I had a bacon sandwich with the builders and it was chaos. Now look at it! It's a dream."

For anyone who has settled for a soggy BLT or, perhaps worse, waited to "dine" on the plane, it's hard to disagree.

Plane Food looks like a proper restaurant, not an airport restaurant. It has a front door and a maitre d'. The chairs are tan calf-skin, not plastic. A specially commissioned £90,000 painting, by British artist Barnaby Gorton, hangs above the bar. Instead of white walls and strip lights, the view through the glass walls is of Boeings and the odd doubledecker Airbus A380 taking off and landing so close you can almost see the faces of the passengers.

The menu looks promising. There's crab with miso and soya beans, organic salmon ceviche with chilli and coriander, steamed wild sea bass with white asparagus, and sorbets for pudding. Turnover will be high - up to 1,000 meals a day - so most of the wines, not just the cheap ones, are available by the glass.

"We're keeping it all very lean, lean, lean. No heavy sauces," Ramsay said. "It's a cross between The Ivy and The Boxwood Cafe, with a touch of The Wolseley. It's going to help make T5 the best airport terminal in the world and turn Heathrow into a symbol of pride."

For those who do not have time to eat in, £14.95 picnics will soon be available to take away and eat on board. "We'll be doing cold dishes, like poached fish, with a bottle of proper wine. If you have kids (Ramsay and his wife, Tana, have three girls and a boy under 10), you can use the coolers for family meals on holiday." If that is, you don't mind doing a little free advertising for Ramsay. The coolers are bright orange and emblazoned with the Plane Food logo.

It may have cost £2.5 million to set up and prices may be low by airport standards - £8 for a starter, £12 for a main course and £6 for a glass of wine - but Ramsay believes the latest addition to his 20-restaurant, 10-Michelin-star gastronomic empire will be his most profitable yet. He has a 10-year lease with BAA, operator of T5, twice as long as most other T5 restaurants.

He has secured the best location in the terminal - just past Business and First Class security checks. Best of all, British Airways is not offering a full restaurant service in its Business Class lounge. "I'm expecting loads of customers from across the atrium," Ramsay said, looking over to the VIP area.

PLANE FOOD is the first of several new departures for Ramsay in London this year. Angela Hartnett, formerly his chef at The Connaught, will open Murano in Mayfair, which will be followed by Ramsay's first solo hotel venture, the 15-room York & Albany, in Regent's Park. Maze on Grosvenor Square will expand, with the opening of Maze Grill, an upscale steakhouse.

Foxtrot Oscar, Ramsay's first £30-ahead bistro-style restaurant in Chelsea, is to be closed and refurbished in response to criticism, notably by the Evening Standard, that it was "cold". Then it will be rolled out across London's high streets and further afield "like a kind of British Carluccio's". There will be more gastropubs, to add to The Narrow in Limehouse and The Warrington in Maida Vale.

Perhaps most significantly, Ramsay will take over his first catering college this autumn. He revealed he has just bought Tante Marie, Britain's largest independent Cordon Bleu cookery school, in Woking, Surrey, in a joint venture with hospitality group, Absolute Taste.

"I'm fed up with the quality of trainee chefs, so my chefs and I are going to teach proper classes. I'm going to be the Brian Clough of catering, with the mouth of Alex Ferguson. The trainees will go to my restaurants to see if they can hack it. There'll be no spending £2,000 a term sitting around learning how to make a f****** Victoria Sponge."

Ramsay may be characteristically bullish but the £15 million expansion comes at an awkward time. The economy is faltering, which will affect air travel and fine dining, and his empire, which now has outlets in Britain and Ireland, on the Continent, in the US, Dubai and Japan, is suffering severe growing pains.

In the past year he has been forced to sack his chef in New York after withering reviews; two of his London restaurants - The Connaught and La Noisette - have closed outright and a third, The Savoy Grill, is shut for refurbishment, with Foxtrot Oscar to follow; he has lost a coveted Michelin star or two; and he has been criticised by influential guides, notably Harden's, which said he had "run out of steam".

After a dinner for critics last week, some French food writers savaged Le Trianon. "We don't give a damn about Gordon Ramsay," said Gilles Pudlowski, who writes France's influential Pudlo guide. Ramsay has also been slammed for "cheapening" his name, by plastering it over £5.99 chocolates sold in Tesco and by advertising Threshers wine.

He concedes that 2007 was "very, very tough" and admits he "made mistakes and learned lessons". He did not spend enough time in New York and failed to pay enough attention to the design of his restaurants. He has now hired new staff and new designers and will spend more time in each of his outlets. Diners and critics will decide if he's upped his game. The reviewers land at Plane Food tomorrow.

One thing, however, is certain: the more he expands, the more his motives will be questioned. The chorus of criticism that he is simply franchising his reputation in pursuit of a fast buck is growing and will become deafening by the end of the year. So, he has decided to get his retaliation in first.

Over a cappuccino, he insists he is not in the game to make endless millions, although of course he likes the money. His personal wealth is estimated at around £66 million. "Money is not the motivation. I got over that years ago. I'm not a businessman, I'm a chef. When I'm not in America, I still cook two nights a week. I actually hate the business bit. I only talk about it because I am the face of the company, but I leave as much of it as possible to Chris."

Chris Hutcheson is Ramsay's father-inlaw and a successful businessman in his own right. He lent Ramsay the money to get started and is now chief executive of Gordon Ramsay Holdings (GRH). He does the numbers while Gordon does the nosh.

Ramsay enjoys the fame Ramsay's Kitchen Nightmares and The F Word generates but he says the TV shows and the ads "are not just about raising profile - they are about business". They generate "huge amounts of cash" - £8 million from Channel 4 and £4 million a series for the US spin-offs - that are ploughed back into GRH.

"You can't make that kind of money from food and, without it, we could not find new talent and finance new restaurants. It would be nice to spend less time on TV but it would, overall, limit what we could achieve." GRH's current turnover is £48 million a year, but is forecast to reach £74 million this year.

Diversifying from fine dining into mid-market bistros and pubs, and selling cheap chocs, is not, he says, addressing his critics, about "dumbing down". It's about creating a more secure business.

"If demand for fine dining dips, demand for bistros will take up the slack. The broader we are, the more secure we are." And the chocolates? "Snobs compare them to what I do at Claridge's but they should compare them to other £5.99 chocolates and they'd see they are the best."

BEING the best is something that Ramsay talks about a lot. He wants it, you suspect, ever since an injury denied him the chance to win honours on the football field with Glasgow Rangers. He is expanding faster than ever with a single, simple goal in mind. "I want to create the most successful diversified restaurant group in the world."

Within five years, he predicts GRH will double in value to £200 million and become the first 20 Michelin star restaurant group, overtaking upscale operations run by France's Joel Robuchon and Alain Ducasse.

"That would be an incredible achievement for a UK firm. That's why I get so mad when people accuse me of spreading myself too thin. It's my f****** money. I've earned it. I could piss it away on living the high life. But I don't. I invest it all in talent here in Britain to make things better."

Which is why, even while he is opening Plane Food, he is planning take his food to new heights. He revealed that he is in talks with British Airways to take over in-flight catering. "Since T5 is a BA-only terminal, it would seem the perfect synergy," he said. "I need six months to get this monster up and running and after that, who knows?"

A Ramsay meal at the airport and another a few hours later before coming in to land? Call him rude. He is. Call him over-ambitious. He's that, too. Call him what you will. The masses at Terminal 2 over Easter would have been first in line.

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