Jamie still shows Naked ambition

"It's an obsession, an absolute obsession. I know I'm slightly peculiar, in the nicest way. I don't give a shit what anyone says: I've seriously pushed cooking to another level, and I am not saying I am a genius or the best at it or anything."

But he is the youngest celebrity chef? "Oh God, yes. Twenty-one when I started. I never said I knew it all. What I did say, from day one, was, like, right, I can make wicked salads. I can make a wicked dressing. I do blinding roasts and I do them a bit different than everyone else. I think I'm pretty damn genius at pasta for a 21-year-old and I make good bread. I never said I could make 30 derivatives of a b?chamel or a demi-glace sauce, but with those four things I could say, 'Come on then. If you want to take the piss out of me, come and do it better than me, come on ...'"

(I later lunch at Monte's and the food is exceptional - only the bill, had they been remiss enough to hand me one, would have spoiled my digestion.)

On television, only he, he says, would have contemplated inserting seven minutes of music into a cookery programme. He compares himself to Robert Winston, making complicated stuff "accessible to Joe Public", but professes surprise that his talent has travelled so well, not just to the US, where 11 million watch him on cable, but almost everywhere.

"I don't know if it's been public yet but I'm the first chef to ever send a book and a programme to France. And Italy. We're nearly in Germany. We're in 34 countries, 64 channels globally. I've been in America and had people from Peru saying, 'I love your cooking programme when you did x and y with that pork', and I'm, like, 'What? You saw it on the Food Network in America?' 'No, no I saw it in Peru.' And I'm like, f***ing Peru! What now? The Inca trail?"

Not quite. His next venture is merely a world stage tour. He does three nights at the gigantic Hammersmith Apollo in September before flying off to Australia and New Zealand. The Happy Days Tour is, he promises, much more than a cookery demo: it is "Friends meets Naked Chef Live", a "dream" he sold to Mark McCormack's International Management Group.

Although his previous theatrical experience was confined to playing an Ugly Sister in a school panto and drums in his pro-am band Scarlet Division, he describes his interplay with the audience at demos these days in the same breath as he mentions Michael Barrymore. But, tell me honestly, given the choice between being a celeb chef and a pop star, which would he choose? "I think every kid would say a pop star," he admits.

Luckily, being a stand-up comic obviously also appeals. When he appeared on David Letterman's show in America (shown here on ITV2), he was warned not to touch the host or feed him anything. "If I hadn't had two years' experience of stupid little producers too worried about their job and not actually about making their people feel good, I would have been crippling myself. But within 30 seconds I had my arm round him, within two and a half minutes he was eating my scallops and I was taking the piss out of him."

Yet Oliver is determined to use his communication skills in higher causes than comedy. "If the wishy-washy Press realised what I do abroad for English food ... I mean, there's no doubt that I am the English ambassador for food. Politicians are selling f***ing chicken tikka masala, right? That's not England. There's so much more going on. If the Press realised the stick that I have to put up with when I'm explaining the passion I feel about England and our food and our chefs, I think they'd shut up. It's them who've written the over-hyped stuff about mad cow disease and stuff. I have to fix a lot of the damage."

On behalf of the future obituarists I try to fact-check a claim he once made that he would like to have his death notice read: "Jamie Oliver brought honesty into TV cooking." Are the beautiful people he cooks for on TV really his friends or are they bussed in from Models One? "No, they're me mates. They'll be a couple of tasty birds there, but if you rewind you'll find lots of Bob the Builders and normal people too." Did he really slide down those banisters to his front door? "I honestly did. They broke in half once. Nearly took my bollocks off."

One thing still concerns me. Two years ago he said he turned down 98 per cent of offers for product endorsement because they would undermine his integrity. So how did the £1million Sainsbury's contract come about, the one that has him goofing around the deli-counter every second ad break? He goes serious. "I can honestly say, hand on my heart, on my life, on my life, that in the last three years I have never made a monetary - is the word monetary? - never made a monetary decision. It's always been about doing something with a bit of integrity."

It was like this. He was frustrated that his local Sainsbury's did not provide all of the ingredients for his recipes so he saw his involvement as a way of raising standards. "What people don't know is that I actually spent hours going into board meetings with their vegetable and herb buyers and basically abused not just their herbs but herbs in general in supermarkets."

What did he say? "A load of crap! Insulting! What do you expect me to say when I bring an Italian friend back and I have to make pesto for four people and I have to buy 14 packs at 89p each of average basil?"

A new range bearing Jamie's imprimatur is now on sale. But Oliver, in his few short years of fame, has not simply raised cooking to new levels, revolutionised TV presentation, invented the situation-cookery-comedy, corrected foreign percep- tions of British cuisine and rescued Sainsbury's herb counter. He has also, apparently, wrought a miraculous transformation in his bride of one year.

"Jools wanted to be a model and undoubtedly she's beautiful. But I don't think she had what it took because she wasn't then feisty enough. She's quite feisty now. I mean, she really came out of herself in the eight years I've been going with her."

The Happy Days press release reads: "His lovely wife Jools will be there to lend a hand."

"Yes, absolutely, and I think I brought her out of her shell."

And how, I ask tentatively, has his ego coped with success? "Initially, it scared the shit out of me. Now, my drive and motivation is quite responsible and grown-up. People never believed me in the early days when I said I didn't care if I was dropped tomorrow. I still don't. At 23, I had a best-selling book for half a year from a cook book that I'd written when I was 17-18 which I never actually thought would get published. When that came out, it was amazing but it was just like, 'God, I'm lucky.' Then the second series comes and it's, like, no, it wasn't luck: you're doing really well now. Fantastic! I won't need to borrow any money from the bank to buy my pub in the country."

Is he serious about this country pub thing? Yes he is: he would bet his life on running one within 10 years, serving five or six covers, living happily there with wife and child - for he is working with Jools on disproving the myth about chefs having low sperm counts because of over-hot kitchens. "I'm not going to be golden bollocks for ever," he says, referring to his TV shelf-life rather than his fertility.

In the meantime, while he still is, Pat Llewellyn, whose voice we hear asking him questions during his programmes, faces a Jamie-less future. I'd heard she was pretty peeved about his defection, but, phoning from a Scottish location on the final series of The Naked Chef, she sounds philosophical. "It's fine. It was inevitable someone with so much energy would become interested in production," she says. "The admiration is mutual," she adds when I tell her he regards her highly, although I am rather understating the case. What he actually says about her is: "She is to producing what I am to cooking."

As you'll have gathered, Chief Chef Golden Balls is well out of control.