First things first. Raymond Blanc is an hour late for our meeting at Le Manoir Aux Quat' Saisons restaurant, but he does not apologise for this - not to me, nor to Harry, the photographer, nor to Harry's assistant. He simply barrels in to the room where we're all waiting for him - it is called, à la Shirley Conran, 'lace' - and shakes our hands (men first: you can forget 'oh la la!' flirtiness when it comes to Raymond: the only people he flirts with are customers, especially if they have cameras in their hands and, well, himself). Then he gets on the phone and gruffly orders tea and pastries. Job done, he tells me that, although dusk is by now rapidly falling, he would prefer to do the interview outside, on the little terrace that comprises this room's private outdoor space. 'Zees is ze most bootiful thing I 'ave seen all day,' he says. I go along with this because, let's face it, he's the star. But it is chilly and, what with the seasons being so muddled these days and there being a pond so close by, I am soon being bitten half to death by midges. Of course, M Blanc affects not to notice my scratching and shivering. Or perhaps he really doesn't notice. He is so self-involved. Once he starts talking, it's almost impossible to get him to stop. Seriously. Even Jeremy Paxman would probably find this task beyond him. 'Let me feen-eesh zees point,' Raymond would say, and Paxo, like me, would have to content himself with picking mournfully at a rum baba or a raspberry millefeuille.

Was he always like this, or has the recent success of his BBC television series gone to his head? The Restaurant was an Apprentice-style reality show in which couples competed to win the chance to go into partnership with Blanc, running their own country gastro-pub in deepest Oxfordshire, not far from where we are right now. Blanc was in the Alan Sugar role, though he's somewhat smoother than the Amstrad boss, at least on camera (if Al is a rough peasant rillettes de canard, Ray is a silky pâté de foie gras; personally, I like peasant food, and think it vastly underrated). The competition was eventually won by Jane and Jeremy, a trainee teacher and an ex-Marine respectively, and their venture with Blanc, the Thatch, will be opening any day. That's where he's been this afternoon, in fact, because it's all systems go and everything must be right. We're just about to start talking about this - 'To the best of my knowledge, I think they can do it; but would I put my hand in the fire [on it]? No, I would not. There are elements you cannot control' - when Blanc's phone goes, and off he trots, down to the end of our garden, and into the public one beyond, where a few guests are still walking off their Friday luncheons. He talks loudly; I can hear him even when he disappears behind a yew tree. After a while, he starts to make his back way to me, which is a relief because, soon, I will need night-vision goggles to see him. But... oh no! What's this? The aforementioned guests are peeking into our garden, and they're grinning and waving their mobile phones. So off he goes again. 'Zay just want a peecture,' he says. In the gloaming, I can see him signing autographs, his arm around first one woman and then another.

Perhaps I look tetchy because, when he comes back for the second time, he gives me a mini lecture - this will be the first of several - about how posing for a picture is the least he can do. 'It's a small price to pay to say a nice word to someone who will pass by.' He's right about this; the Manoir is very expensive, and those who cough up for its elaborate two Michelin-starred tasting menu have every right to be treated politely. Nevertheless, I can't help but feel that, in this instance, he didn't have to rush out to talk to them; it was almost as if he had deliberately drawn them to him. Also, not 10 seconds ago, he was telling me how much he disdains celebrity: 'I hate it. Ten years ago I did a programme with six million viewers. I was at the height of my acclaim. I was young, beautiful and sharp. But I'm not affected by all that nonsense. These things will never touch me - not even zat (using his thumb and forefinger to indicate half a centimetre) much!' Which is fine, except people only want to take pictures of him on their phones because he has been on the telly and is therefore, in their eyes, a celebrity. I bet no one goes into say, Moro, in Clerkenwell, and asks to take pictures of its cooks, no matter how much they've enjoyed their dinner.

In the past, Blanc, now 58, always said that he would never do reality TV; he thought it was moronic and voyeuristic, and he wasn't willing - unlike some he could mention - to indulge in on-screen bullying. So what changed his mind? 'Don't think I came out of semi-retirement by accident,' he says. 'Eight years ago, I didn't want to do Bazalgette [maker of Big Brother] TV. So hollow! No information, no intelligence! But I've known for three years that television must become more conceptual, more exciting, more educational. When they came to me, I immediately liked the idea. Being a self-taught chef myself, I wanted to give a chance to young people.' He was genuinely touched by the couples' commitment. 'Absolutely! I love to be emotionally involved. It's very much my story. When I came to cook in England, I took that frying pan and I knew it would change my life and it did.' So what's so special about Jeremy and Jane? 'Desire! Some people only dream, and some people want to make it happen. Big difference. At first, they weren't a team. If you're a Marine, you spend most of your time away. You only see your wife once every six months. You could see he had no time for his wife. He was short-tempered. He was a pig. But as the series went on, they became a couple. Jeremy also keeps a clean kitchen, as you would expect from a Marine.' But what about Jane? She was a real Tiny Tears, always weeping in corridors. 'Our lovely Jane. She was called the Crying Lady. To explain her secret... I have a young woman here. A woman will behave entirely differently from a man to release that pressure. If she is uncomfortable, a woman will usually shed a few tears in a private place. A man will shout or scream or hit a wall. The tears of Jane didn't bother me at all. They were private; little did she know that there were cameras all over. But she never cried in front of guests.'

I tell him - I know this is hardly a revelation - that the disjunction between what British people watch being cooked on television (turbot, sauce vierge) and what they cook at home (fish fingers, sauce rouge) grows almost by the day, and that I find this increasingly perplexing. 'Voilà!' he shouts. 'There, I have a place. I'm that craftsman! I have the deepest understanding and respect for the seasons, the locality, the skill...' Right, so what does he fancy for dinner tonight? For a second, he's stumped (which is odd; this particular question never stumps me) and then he says: 'Maman Blanc's apple tart. Do you want the recipe?' Maman Blanc is his elderly mother, and he brings her up at any opportunity, because he likes nothing more than to talk about his working-class roots. His father was a watchmaker, and Blanc, who is one of five children, grew up in Besançon, in Franche-Comte, where the onions were sweet as honey, the chickens as free as, well, birds, and the pastry shorter than Napoleon. It's a background that he has gilded over the years so that it now sounds impossibly corny, sort of Marcel Pagnol meets a Stella Artois ad - or, perhaps, the Gallic equivalent of that old Monty Python joke about Yorkshiremen living in a shoebox in the middle of the road ('It was tough, but you learned respect'; 'My mother is like a mountain goat. She cooks like an angel'; 'I helped my papa build his house. Those men would work 10 hours in a factory and then go home and grind up rocks to make cement'). Anyway, to get back to his supper. Apple tart doesn't count: I was thinking more along the lines of meat and veg. 'I've known for years that meat is carcinogenic. Our intestine is eight metres long. A dog or a bear has just got a tube, and it goes in and it goes out.' Right. So he doesn't eat meat. 'Of course I eat it. But I'm selective. My breakfast changes all the time! If you only eat egg and bacon, you get the serious problem of malnutrition.'

Blanc's parents had wanted him to be a draughtsman but, having tried about 20 different jobs from nursing to watchmaking, he decided instead to be a chef; the moment of epiphany came in Besançon, in the Place Victor Hugo, where he watched waiters on a terrace in their black ties carving meat in the moonlight, and thought: oh my God - this is it. So, by way of a start, he, too, got a job as waiter. He came to Britain in 1972, ostensibly to improve his English but also because, in Besançon, he'd crashed into an English girl carrying a tray of drinks, and when she apologised, her accent was just so darling... well, what can you do? He had fallen for les Anglais, even before he arrived. In Britain, he got a £13-a-week job as a waiter at the Rose Revived, a pub restaurant in Oxfordshire, and spent his time furiously flattering the head chef while secretly despising the 'depressing piles of beige and grey food' he put on to diners' plates. Soon, he was helping in the kitchen.

Meanwhile, he started seeing the boss's daughter, Jenny, who later became his first wife (they have two grown-up sons, Olivier and Sebastian, but were divorced in 1985). Together, they ended up running the Rose Revived until, five years later, they opened their first restaurant in Oxford, between Oxfam and a ladies' underwear store. 'On the wrong side of town, just red-and-white-checked tablecloths. We mortgaged our little house, and we put every penny into the food.' Within two years, it was one of the best restaurants in Britain (though he wasn't the best businessman; at one point, his debts were nearly £1 million).

He opened Le Manoir in 1984, and loves to tell the story of how he found the 15th-century manor house - it was then in terrible condition - while riding around on his motorbike. 'It was like falling in love,' he says, and it is certainly true that it's a beautiful place, with its walled gardens - reputed to supply the restaurant with 70 per cent of its vegetables - and its rolling lawns. The restaurant has held its two Michelin stars for two decades, and many of the most famous chefs in Britain have done stints in its kitchen (Michael Caines, John Burton-Race, Eric Chavot, even Marco Pierre White). But Orient Express now own the majority share, though he remains its figurehead. His chain of brasseries, Le Petit Blanc, was sold to the Loch Fyne Restaurant group in 2003 after it went into administration; Blanc retained a 25 per cent stake (it's now run as a spin-off from the Loch Fyne group called Blanc Brasseries).

Does he have any regrets? Not at all. 'How many mistresses can a man have, and take pleasure in them all? I'm happy. I've got all that I want, and I feel privileged. I love England!' His happiness has been further increased by the woman in his life, Natalia Traxel, a 30-something Russian-born doctor and former Manoir regular, whom he wooed assiduously, in the French style, until she finally submitted to his charms (he would read Oscar Wilde to her, or call and say things like: 'I have to see you now; I found a beautiful leaf on the Champs-Elysées and I want to give it to you'). They were supposed to be married this year (this will be his third marriage; his second wife, Kati Cottrell, was a psychotherapist) but, alas, it hasn't happened yet. 'No, not yet. But soon. It may happen in the Maldives some time. It will happen just like that. We're committed to each other. We love each other.' When he gets home late at night, 'lovely Natalia' rustles up an omelette for him; they live, with her daughter and the 1905 Bechstein grand piano that he gave her for a birthday present, nearby.

What fascinates me about Blanc is the fact that he stuck around in Britain for so long, even though, as he is always telling us, we don't know anything about food, nor do we particularly care about it. Once he had his stars, why didn't he just go back to his beloved France? Apart from anything, one assumes it would be less expensive to run a smart restaurant there. I try to ask him about this, but for some reason he takes the question as his cue to give me his thoughts on the state of food production. 'In a year's time, you are going to look at food differently,' he says. 'Seriously.' He sticks out his hand, and I have to shake it, as if we're making a bet. Then it starts. First, he tells me 90 per cent of British people want a £2 chicken. Well, that's disgusting. 'No, no, it's not disgusting. It is what it is. We are so separated from agriculture, it's unbelievable.' From here - I'm going to summarise because the unexpurgated version is on the long side - he takes me through pollution, the food chain, agro-chemicals, intensive farming and the concept of shelf life. He tells me about these things as though they'll come as news: as though, in fact, I'm a moron who has never read a newspaper, much less worked on one for the past 16 years. At one point, he asks me if I've heard of the Stern report. Er, yes. It looked at the economic consequences of climate change. He looks disbelieving. 'Well, you will be amazed at the blissful ignorance and lack of interest in it!'

This rant lasts nearly 20 minutes, and it twists and turns like a mountain pass. I try to interject half a dozen times, but whenever I do, he either raises his hand to silence me - I am going to send him Lynne Truss's book, Talk to the Hand, for Christmas - or he all but shouts: 'Let me finish!' His point seems to be, when I boil it down, that if we start to care about food, this will have tangible benefits for society.

'Our society is about winning at any cost: I want it, and I want it now, and I will sit on you to get it. We don't give a f*** about our neighbour. He can piss off. But if we eat together, if we meet at the table for good, simple ethical food, we can create a kinder society. It's not rocket science that if I don't know you, I can't become your friend. In France, working-class people have a culture of food, and when I use the word "culture", I use it with huge reverence.' I wholeheartedly agree with him about the importance of ethical farming, local produce and all round green-ness. Greedy supermarkets, excessive pesticides, mass production, profit to the exclusion of everything else: who needs these things? Only it's not me he should be lecturing, but the kind of fat cats whose Bentleys and Porsches are in his car park. Also - and this is a tiny point - isn't The Restaurant a perfect example of something that pushes patience and hard work aside in favour of instant results? A chef takes years to learn his craft; the couples who appeared in The Restaurant had only a few weeks.

It's pretty dark now, so I thank Blanc for his time. 'Isn't there anything else you want to ask me?' he says. What? He kisses me goodbye - both cheeks - and off I go. Look, I think Blanc is a fine cook, and I know for a fact that his staff are fond of him, and that his series was a big and unexpected hit. But he is also exasperating beyond words. Lots of chefs - most, in fact - are control freaks and ego-maniacs; it comes with the territory. But he also sees himself as a romantic (or, perhaps, he long ago decided that this is what we English expect him to be). The stagey arm-waving; the impassioned monologues; the self-reverence: these things are so exhausting. In my taxi, I can hardly keep my eyes open. I am, however, sufficiently awake to hear the driver tell me that the last time he picked up 'RB', it was three o'clock in the morning. The driver asked Blanc if he wanted to be taken home. But, no: M. le chef had other ideas. 'Take me to a place where I can see the sun rise!' he said. Honestly. Frenchmen. I admire their ways with asparagus and duck, but for their grand gestures, I care very little.

Le Manoir au Quat' Saisons, Great Milton, Oxford; 01844 278881; The Thatch, Lower High Street, Thame, Oxfordshire 01844 214 340.