Pucka up, America: How Oprah Winfrey could help Jamie Oliver crack the States

The South Beach sunshine is splitting the palm trees in the fantastically froufrou garden overlooking the pool at the Delano Hotel. In the midst of this Miami cliché sits Jamie Oliver, the epitome of the Brit abroad, mulling over the question of how to crack America. But he's not being given much of a chance – every few minutes a passer-by butts into our conversation ("I'm your biggest fan!") and pulls out a camera. On each occasion he is polite, patient and poses with a trademark grin. "I love that," he says, as we're left alone. "They always say 'Sorry to interrupt', then they start talking for 10 minutes. Being known in America, it's horrible. Imagine being really famous here..."

Oliver is in Miami for the South Beach Wine and Food Festival, halfway through his annual promotional tour of the States. Now in its seventh year, the festival is a four-day fandango of eating, drinking and celebrity-chef appearances, housed in a series of tents on the beach, and sponsored by The Food Network, a cable channel beamed into 90m households across the US, and which airs Oliver's programmes.

This is a crucial year for the chef. His lucrative relationship with Sainsbury's, the supermarket chain he's been paid handsomely to advertise for eight years, went through a rocky patch at the start of the year, after he attacked it for failing to get involved in his TV documentary about factory poultry farming; the 32-year-old is braving new waters with an ambitious branded restaurant concept set to launch around the country; and he's having to fight back to regain his title as Britain's biggest TV chef export to the US, after being overhauled by Gordon Ramsay. With help from Oprah Winfrey, he might just do it... if he can be bothered, that is.

"I've been coming over to the States six weeks a year for the past eight years and it's too much," he says. "I'm grown up now, I've got kids, family and plenty of responsibilities in England to be getting on with. It's a big investment to come here. You tour around doing all the shows – Letterman, Ellen, The Today Show, Good Morning America. It's kind of soulless and not where I'm happiest. I like to be cooking and writing – that's easy and effortless by comparison."

So far in his career he's made only one programme with the US market in mind: Oliver's Twist – essentially The Naked Chef, but in which he presented the show to camera or spoke to a guest, rather than speaking to a producer off-camera. "It was 52 episodes but I don't ever want to do that [many shows] again because it just wasn't my cup of tea," he says. "But there's really only one way to break America and that's to keep coming up with shitloads of telly, and I'm never going to do that. They think I'm the biggest pain in the ass in broadcasting. I give them four episodes of this and six of that. But if you want to go up the next gear you've got to go to Gordon Ramsay's level. He came to America about four years after me and he's done a great job. He's a big deal and has two good formats behind him in Hell's Kitchen and Kitchen Nightmares..." He pauses. "To be honest my living is books – and Americans don't buy a lot of books. I've been here 10 years and I've had books at number one in the charts and they've all been in the top 10 – it's really not that hard to do in terms of sales. So I'm not sure why I'm here really," he laughs.

Luckily his American PR knows exactly why he's here: to push his appearance on a new US reality show that sits in a primetime CBS slot previously occupied by Desperate Housewives, a show that could potentially make him a household name in America. "I was just about to say, that's it, I'm going to pare it right down to a couple of weeks a year here. And then Oprah phones and everything changes – as it does."

The doyenne of America daytime television was calling to invite him to be a judge on Oprah's Big Give, a new Sunday-night primetime spin-off from The Oprah Winfrey Show. Oprah's Big Give took to the air in America last month, and is getting "big numbers" in the US TV ratings. It has already propelled Oliver to the cover of the glossy TV Guide, the US's premier listings magazine, giving Oliver a profile he's never managed before. "Not for cooking, which is a shame, but cooking doesn't really get big time over here," he says.

"Oprah wanted me to be a judge because of the work I'd done with Fifteen [a social enterprise founded by Oliver that helps wayward youngsters gain catering qualifications]; all the judges either have charities or run them. Although it was a weird job for me I felt really equipped to do it," he says.

"One day on her daytime show Oprah basically gave everyone in the audience $1,500 and a little camera and said, 'Here's the camera, here's the money, here's the twist: you've got to do something good with the money.' A month later all the tapes came back in and there were 20 crackers that were fantastically entrepreneurial. What had the potential to be really sugary and naff actually came across really well. I don't know anyone who has ever said no to Oprah and I wasn't going to be the first. No one in the world makes me nervous, but she does. It sounds like bollocks but she's on a different level in terms of her thinking and her power."

The contestants on Oprah's Big Give compete to see who can do the most good. A TV executive would probably pitch it as Philanthropist Idol or The Good Apprentice. Oliver sees it as "a reality show about good shit instead of bad shit. It highlights lots of really important social issues, from physical and sexual abuse, to homelessness and orphanages, to soldiers that had come back from Iraq in a mess. It actually was a pleasure to do and it had me in tears several times."

If he has one worry about the series it's that he sometimes comes across like Simon Cowell with a social conscience. "On one of the programmes, where this guy had come up with something really crap, there's me going, 'Emotion – not good. Strategy – not good. Presentation – not good. What's going on?' I was Simon Cowell. When have I been like that? But of course the Yanks seem to love all that." '

Whether or not Oliver appears in the next series of Oprah's Big Give, it seems unlikely he'll be spending as much time in America as Ramsay in the foreseeable future, as he's just about to launch that new restaurant brand in the UK; the first branch of Jamie's Italian will open in Oxford in early June. Billed not as a chain but as "a collection of neighbourhood restaurants", Oliver wants Jamie's Italian to bring affordable all-day dining to university cities. A second branch will open in Bath in August, a third in Kingston by the end of the year, with Brighton and Cambridge to follow in 2009.

"I'm passionate about doing something for university cities. My local city's Cambridge and there's almost nowhere to eat as far as decent, affordable, everyday stuff goes. I'm not interested in doing London for a bit, if ever. I'm bored with London. We had investors set up for something in London – I was going to put in £500,000, they were going to raise £7m to do the first five restaurants – then they started shifting the goalposts at the last minute, so we told them where to go," he explains. "So now it's all my own money, with my house and everything thrown in as a collateral and just one very small shareholder, and that's my business partner who runs everything with me. It is definitely the most important thing I'm going to be doing for the next five to 10 years.

"The idea is to make it about really good, predictable fresh food based around the world of antipasti and tapas, with fresh pasta home-made on site. Each restaurant will have a big grill and I'm getting these panels made by this guy in Gloucestershire so we can cook stuff al Mattone – 'on the brick' – screaming hot. It will be somewhere you can go for breakfast, lunch and dinner. You'll be able to go there and get out for £13 or, if you want the whole three-course thing, it will be around £30-something a head.

"Most of the graft has been on the format of the thing and the sourcing of the ingredients. We've got free-range chicken on the menu at £10.50 a go, whereas most gastropubs are whacking it out at £14-£15. Our main aim is to make it good value. If we're busy we can keep the prices down. But they'll be good-looking restaurants, with £1.3m fit-outs, proper kitchens, with the chefs and senior staff paid really well.

"Anyone can bash out a bunch of restaurants; the challenge is, if it's me, there are expectations, and that's scary. The whole Italian fresh pasta thing, I love it and I don't really think that it's been done that well yet, certainly not nationally. There's a load of competition out there: Piccolino, Carluccio's, Strada – none of them are crap, we've all got views on them. But it's not like 10 years ago when all we had was Bella Pasta. I want Jamie's Italian to be somewhere you can put a shirt on and take the mother-in-law if you're a student."

Which is all very well, but even Oliver must wonder whether he's taking on too much. Fifteen, for instance, takes up a lot of time, with its restaurants in London, Cornwall, Amsterdam and Melbourne. "The reality is that I'm a chef and I was always going to need to open my own restaurant at some stage. Fifteen will always grow, we've got a good structure in place and we've worked hard to get consistency and financial stability. Probably in the next two years we will do South Africa and in the next four years we might do Berlin. There's also the possibility of, as we did in Cornwall, working with a local development agency to open one in Leeds."

If Oliver talks as if he's heading up a global empire in his famous mockney tones, that's because he is, more or less. His programmes are shown in around 50 countries across the globe, closer to 80 if you include the broadcasts on BBC World across Asia and Africa, and he's been dubbed into Icelandic, Lithuanian and Arabic. His office gets press enquiries from places as far-flung as Taiwan, Israel and Kazakhstan. His typical week might be divided into filming for Sainsbury's, promotion for his retail division that sells everything from extra-virgin olive oil to pesto, and work for Tefal, for which he promotes a range of signature cookware. Then there's filming for whichever TV series is in production, work on the next book, and meetings for Fifteen and Jamie's Italian. Then, when he has time, he works away at a kitchen he had built in a barn beside his house in Essex (he has a second home in Primrose Hill in London), where much of his last series, Jamie at Home, was filmed and which doubles as a development kitchen. All of which has to be fitted in around weekends off and seven weeks a year on family holidays.

Recent estimates of his personal wealth being in the region of £25m may or may not be accurate, but over the years he has surrounded himself with a team of advisers and colleagues who form a formidable money-making machine, whether it's through publishing, TV production, merchandising or managing endorsements.

On the matter of his Sainsbury's endorsement, he says "All is good". The chain pays him £1.2m a year to front its ' advertising, but chief executive Jason King was understood to be less than impressed in January in the wake of his criticism of the retailer for not turning up to a public debate on chicken farming in his Jamie's Fowl Dinners programme on Channel 4 . That led Oliver to send an open letter to Sainsbury's staff, apologising for the outburst, followed by full-page newspaper ads from the supermarket stressing the quality of its poultry. "It's complicated; I wish it wasn't so fucking complicated," the chef admits. "I've been working with them for a long time and I don't think you can have any staying power unless you are honest, regardless of whether what you are doing is a good or a shit idea. I really do think it's my responsibility – it doesn't matter who is paying me – not to lie to the public. As soon as I do, I'm in trouble."

There is a cookery demo ("fish stew, pasta dish and a salad") to do back at the festival, where Oliver is the afternoon's headline act, so we leave the froufrou garden and make our way along Miami Beach towards the huge tents overlooking the Atlantic. I mention Anthony Bourdain, the author of cult chef memoir Kitchen Confidential-turned-TV chef, who is also appearing that afternoon at the festival and who in the past has been less than complimentary about Oliver.

"You're going to think I'm a bit of a pleb," he says, "but I've never actually read a book from start to finish because I'm dyslexic. If I read 30 pages, even if it's for my kids, I'm asleep. It doesn't mean I can't read or I'm stupid. It just means I'm more of a browser, like with cookery books and magazines. But the only book I've read cover to cover is Kitchen Confidential, which I loved. Then the paperback comes out and there's a quote on the back that says I'm a choirboy. I was gutted he apparently thought I was an asshole. But things have changed. If you go back, Marco [Pierre White], Gordon [Ramsay] and Anthony [Bourdain] were all having a go at TV chefs and now they're the ones knocking out loads of TV. I've never met him but I imagine Anthony used to hate me because he thought I was just some cocky little TV chef."

It's a revealing moment. Could it be that everything Oliver has done since The Naked Chef, when he started controlling his own career, from his work with Fifteen to School Dinners and the new restaurant, is an attempt to get respect from the cynics who dismissed him in the early days as nothing more than a mouthy moped salesman? A clue comes on our way to the demo, when we run into Bourdain, who smiles and shakes hands with Oliver. "We meet at last," Bourdain says, "I guess I owe you an apology," before adding, "I loved Jamie's Italy." As Bourdain wanders off, Oliver turns back to me with a grin – and not one of those slightly forced ones he keeps for his "biggest fans".

The first branch of Jamie's Italian will open in early June at 24-26 George Street, Oxford (www.jamieoliver.com)