At the end of this month three modern icons - fast cars, striking architecture and urban food - come together in a former Post Office by the vegetable stalls of Berwick Street market in Soho.

The Igeni building, created by Richard Rogers, will emerge from the cladding to house the offices of the design team behind the next generation of Ford motor cars. But most of the ensuing publicity will revolve around the ground floor and basement which will house Alan Yau's latest and most egalitarian restaurant, yauatcha (sic), and comprise a teahouse, a pastry shop and a basement serving dim sum from 1000 to midnight seven days a week.

Even to those who know him well, which I expect is only a small number, Yau is a phenomenon among restaurateurs. He was the man who conceived and created Wagamama, the original noodle bar chain which under other's management has now spread across the south of England and most recently opened in Sydney, Australia. He then spent £2 million converting a National Westminster Bank on Wardour Street into Busaba Eathai which now boasts sales of over £3 million a year on an average spend of just £12.60.

And Yau is, I am delighted to say, the proud Chinese restaurateur who read my article in January 1997 lamenting the lack of any Chinese restaurants in London to match those of Singapore or Hong Kong, and persuaded his backers to spend £4.5 million on converting a former car park in an otherwise dreary cul-de-sac behind Tottenham Court Road into Hakkasan, which on a busy day serves 800 customers, making it probably the second biggest grossing London restaurant after Nobu (although having secured an initial rent of £8 a sq ft and the best sites are now commanding £40 a sq ft) Hakkasan must rank as the most profitable.

Over lunch at Fino restaurant, Yau talked but certainly did not behave like the big businessman. He had just flown in from Moscow where he had his arm twisted to act as a consultant to Shatush, a Chinese restaurant, which some Russian night club owners said they were going to open and model on Hakkasan whether he helped them or not. And he had just had a phone call from a successful Canadian property developer who wanted to franchise Hakkasan. "I replied that I don't believe restaurants can be franchised successfully but that if he had the passion and the money he could easily copy Hakkasan - as long as he does not use my name." The smile at the end of this comment seemed deceptively gentle.

But even cool-as-a-cucumber Yau cannot hide his enthusiasm for yauatcha and not just because Tim Yip, the Oscar winning costume designer responsible for the film 'Hidden Tiger, Crouching Dragon' will design the waiters' outfits.

What particularly excites him is that he and his approach to good value food for all were sought out by Ford. "J Mays, Ford's director of design responsible for cars like Jaguar and Land Rovers, wants to move his disparate design teams into an urban environment similar to the one that their customers live in. And he wants them to enjoy good quality, urban food which they can afford every day whenever they want it."

yauatcha gradually emerged as a vehicle for Yau's personal and professional dreams. " I am Cantonese and therefore I have always longed to open a tea house because drinking tea, and sharing food whether it is a pastry or dim sum, is, we Chinese believe, the most informal social banter that there is. It is our equivalent of going down to the pub."

Yau even finds the proximity of the fruit and vegetable stalls highly propitious. "My parents, who brought me up running their Chinese take away in Peterborough and Kings Lynn, have now gone back to Hong Kong. They get up every morning, go to the market to buy food for the rest of the day, and then go and meet their friends in a teahouse to share breakfast. It is what I hope will happen at yauatcha."

But however similar the food may be - and Yau has hired Stephane Suchata, a top French pastry chef, a master dim sum chef from Singapore and Hsieh Chih Chang, a tea mistress from Taiawan to ensure authenticity - what Yau's parents find difficult to understand, despite their obvious pride, is quite how their son can be so successful at delivering what is so basic to so many.

It is a question which baffles him. The only time Yau seemed lost for words was when I asked him directly to explain his success. What finally emerged were some obvious factors if no blueprint.

"You must begin with the end in mind and then be prepared to devote time, energy and passion to make it happen. Hakkasan took three years, yauatcha two and a half and did include three complete redesigns and three different sets of fees from Christian Liaigre, the interior designer, and will now cost £4.2 million. I suppose if I have a particular skill it is the ability to walk into a building and envision how it will operate successfully, not just where the customers will sit or where the kitchen will be but where, crucially for example, the waiters stations and the electric terminals can fit. Space planning and a sense of ergonomics are crucial."

There are other strands. Yau is not surprisingly a control freak albeit one maturing gently after the loss of Wagamama and the less than successful Anda on Baker Street. When he was offered the Busaba Eatthai site by a potential partner his response was "only if I am in charge" so that, again in his words " I could make the place not just work but fly."

Yau is also aware that not only is he living through the golden age of the restaurant but that he has been operating at a time when all thing Asian, and particularly Asian food, have become ultra-fashionable. "There are really only four different food styles which can easily traverse the globe: Japanese sushi, Middle Eastern mezze, Spanish tapas and Chinese dim sum and when I began there was the infrastructure to make Asian food successful - after all sushi and dim sum have been around for centuries - but not the individuals to glamourise them. But then in the 1990's along came Nobu Matsuhisa in Los Angeles, David Thompson in Sydney who elevated Thai cooking to a new level and Su-Sur Lee who did the same for Chinese food in Toronto. Asian food is visually exciting, healthy and fresh." In Yau's hands it can also be extremely profitable.

But the most fascinating aspect for Yau is making these individual restaurants work. "By Christmas there will be a staff of almost 500 and I want the whole to gel," he explains. And this despite an aversion to franchising or developing a Hakkasan brand. "What differentiates restaurants from retail is that if you want to maintain quality a restaurant must have its manufacturing and retail units under the same roof and ideally as close together physically as possible. That is what so many chefs don't appreciate when they try to become restaurateurs. Outside the kitchen there are just too many strings to be pulled. They should stay cooking or do what Ferran Adria does with El Bulli and only open for six months a year, running it not as a business but as a way of life."

My huge regard for Yau only fell at the end of the meal when I pressed him as to why he was flying out to Hong Kong the following day just before yauatcha was due to open and most of the menu was, as he confessed, 'still in my head'.

"I have been approached by one of the big property companies to look at a site for a possible restaurant. Personally, it is a huge compliment to be invited back into the heart of the dragon as it were to see whether I can set up my kind of Chinese restaurant over there."

This return to Yau's spiritual home would be a fitting tribute to all that he has achieved for London. As far as he is concerned, the success of Hakkasan has been twofold - in offering the best possible Cantonese food to Londoners and providing the Chinese community with a taste of home cooking.

What has most surprised Yau about this is that the average spend at Hakkasan is the reverse of most other restaurants in that it drops substantially at the weekend. "During the week we have customers who order dim sum, then items from the a la carte menu and drink cocktails and wine. At the weekend we get Chinese families who only drink tea and only order dim sum and spend about half as much as those during the week."

But this is a further tribute to all that Yau has created. His vision of Wagamama has converted thousands of teenagers to the pleasures of eating out and to eating healthily. No other restaurateur has created restaurants where so many will queue for so long, have fun and leave wanting to return. Personally, I hope that his Hong Kong trip comes to naught - Britain still desperately needs him.