How we met: Marco Pierre White and Yiannis Kitromilides

Marco Pierre White, 38, is the superstar of British haute cuisine. He was the youngest chef ever to be awarded a Michelin star, and the first British-born chef ever to win three Michelin stars. He opened his first restaurant, Harvey's, in 1987. In 1993 he moved to the restaurant at the Hyde Park Hotel, and in 1997 opened the Oak Room in Piccadilly. This year saw the opening of the Mirabelle, in Mayfair. His sixth restaurant, Titanic, opens on 1 December. He lives with his girlfriend, Matilde, and has three children. Dr Yiannis Kitromilides, 53, is an economics lecturer at the University of Greenwich. Born in Cyprus, he came to England in the Sixties to study at the London School of Economics. He has been friends with Marco Pierre White ever since visiting Harvey's as a customer shortly after it opened

MARCO PIERRE WHITE: If my memory serves me well, Yiannis came to Harvey's one lunchtime and sat on table six. I actually remember what he ordered all those years ago. He started with a nice nage of scallops and shellfish. He came back to the restaurant nearly every week after that, often by himself, and enjoyed my food. I got to know him slowly and he became my favourite customer. That's how our friendship started.

My first impression of Yiannis was that he was above all a gourmet - obviously a professional man - and extremely sincere. The thing that intrigues me about people is when they are enthusiastic and display interest. What I loved about Yiannis was his enthusiasm towards food and life. He is a man who has a tremendous affair with gastronomy: he was a great believer in Harvey's and a great supporter of the place.

Our friendship was based at first on food, but when you see a person regularly - as we saw each other - you talk about what you're going through and what you're experiencing. Life is not a smooth ride: there were times when I was down and I would talk to Yiannis and there were times when he would talk to me about what troubled him. Friendship is about giving each other time and Yiannis and I did that.

We spent a lot of time talking. The uniqueness of our friendship is that Yiannis is not only my friend but also my customer, and that's unusual. I like my clients to feel welcomed and I'm friendly with many of them, but to really be friends is something very different. When Yiannis walks through my door, it's like my brother walking in - he is always welcomed. We pick up from where we left off, no matter how long it's been since we saw each other. With most people when they come here, even if I was feeling terrible or having a shit day I would smile and say, "Good morning, how are you, come in ... " and so on, and they would never know I was in a bad mood. People don't want to know that things aren't going too well: they've come in to enjoy themselves, have a glass of champagne. With Yiannis, there is a high level of honesty. If he walked in and I was feeling shitty, he would know and I wouldn't have to hide it. I can have any conversation with him, that's how deep- rooted our friendship is. We've known each other for 12 years now. When we were both going through our marriage break-ups, we were there for each other. Yiannis would come to Harvey's and I would cook for him. It was a way of comforting him, of cheering him up. On the day when my daughter Laetitia was born - 20 September 1989 - Yiannis was at the restaurant, and when I told him I had to rush to the hospital he jumped in the car with no hesitation and came with me.

What confirms that Yiannis is really special to me, nearly 12 years down the line, is that there has only ever been one other client who's come anywhere near as close to me. He's a wonderful man too - another eccentric loner who reminds me of Yiannis very much. Yiannis loves to dine alone, although I know it has to be a very special restaurant for him to want to do so. He is content with his own company and with gastronomy and at the end of a meal he wants to talk about it. He's no fool: he's a man who is strong and confident enough to say to me, "Marco, I think this was a bit undercooked," or to say that something didn't quite work, or that something was the best thing he'd had in his life. Shortly after we met, he said to me, "Marco, that first day, when I had the seafood nage, I knew you were a great chef." He's really loyal and has followed me around in all my restaurants, and he is certainly a much bigger man than he was when we first met, but come to think of it so am I! Those early days at Harvey's though, with the highs and lows, were very special. I do wind him up sometimes - for example, if I haven't seen him for a while I'll say to him, "Where have you been?" I always know when he's been going astray and trying out other restaurants ... I'm the woman in the relationship and he's the man and when he goes astray I have to get him back! Yiannis has tremendous love and affection to give and you can't expect him to give one person all that.

DR YIANNIS KITROMILIDES: For most people, eating out is a hobby. For me, it's a passion. I'll travel any distance to try a new restaurant. The first time I went to Harvey's was on 14 February, 1987 - within weeks of its opening. It was a Saturday night, a friend was visiting from Crete, and we wanted to go out for dinner. We were oblivious to the fact that it was Valentine's Day - Greeks don't normally celebrate this event - and everywhere we tried was fully booked. The manager of one of the restaurants I was a regular at mentioned to me that there was a new chef worth trying. He'd worked at the top four restaurants of the day, and his name was Marco Pierre White.

So, stuck for a restaurant, we decided to try this new place. Wandsworth was a long way from north London, where I lived, but that first meal was unforgettable - and not only for the food. We finished our first two courses and were waiting for the dessert when suddenly we heard a big commotion coming from the kitchen with the sound of pots and pans crashing and people shouting. The whole restaurant went silent. Then a woman sitting near me announced, "We have an artist in the kitchen!" We were all stunned, wondering what next, when a tall, thin, long-haired guy came rushing out, took a quick look at the dining room and went back into the kitchen. He looked more like a rock star than a chef. That was the first time I ever saw Marco, and we've always referred to that evening as the "St Valentine's Day massacre".

That first visit left me captivated: it was wonderful to taste such food. As we were leaving the restaurant, I told the apologetic manageress not to worry, that this was going to be the best restaurant in town. As I often went back alone, Marco must have realised I was there just for his food, and one day he came out of the kitchen and made for my table. He sat down and asked me what I thought of my meal, and that's how we started talking.

What intrigued me was his almost Mediterranean openness - he's half Italian - and that he was interested in my opinion on food. What was touching was that when I used to arrive at Harvey's, a waiter would often come to my table and, as if by Royal Command, would say, "Mr Yiannis, can you go into the kitchen, please? Marco wants to talk to you." I'd go in and Marco would ask what I wanted to eat and then he'd cook it for me. After the meal, he'd join me and we'd have coffee together. That was when we spent time talking, and although our friendship began with a mutual love of food, it grew deeper and closer over the years. This is the friendship of two men sitting in a restaurant around a table talking about everything. We became friends well before the media hype began, and our relationship has remained the same. Marco, too, has remained the same. He's a really decent, nice, generous man - volatile and mercurial, of course, but that's one of the things that make him special.

One night, I arrived at Harvey's very late without booking, feeling depressed because I was going through my divorce, and Marco immediately picked up on it. He ordered me to sit down, relax, have a glass of champagne, and he announced that he was going to spoil me by cooking all my favourite food. I had tagliatelle of oysters with caviar; panache of foie gras; scallops with jus de Sauternes; a salad of red mullet; roast pigeon from Bresse, accompanied by a ravioli of wild mushrooms and fume of truffles. Pudding was biscuit glace with a hazelnut praline. After the meal, when the restaurant was nearly empty, he sat with me, and was very sad and supportive.

Marco is a very clever, articulate man, and combined with his incredible talent it is not surprising that he is successful. We're very different characters and we live very different lives. I am an academic; he is a star. Once, when he was having one of his books published, he discovered I was about to have one published too. He was keen that we should have a joint launch - until I mentioned that my book was on political economy! He says I'm an eccentric loner. I may be an eccentric, but I'm not really a loner. It's just that eating out in good restaurants is such a passion, and sometimes I will dine alone. My friendship with Marco developed because I was on my own so often. I'm really thrilled with his new restaurant, the Mirabelle, because it brings back fond memories of Harvey's.

Although now we don't spend as much time sitting at a table talking, whenever we meet there's always a genuine sense of warmth and understanding between us. Marco often asks me to go fishing with him, and I hope he's not offended that I never have, but part of me feels that our friendship is so intrinsically tied up with sitting around a table in a restaurant that I don't want to change it.