How did you get into cooking? "I am a third generation chef on my father's side. Our family has a restaurant in Sardinia and, when I was growing up, I was always in the kitchen. My dad told me, 'If you want to do this job, you have to go abroad.' I went to London, Milan, New York, Paris; I worked for Marco Pierre White and Marchese Piero [Antinori]."

What did you like about being in the kitchen? "Everything. My grandfather had a big garden and today we still grow everything - lemons, oranges, all our vegetables. We live by the sea and have fresh fish. When customers come to my restaurant, they come to my house as my guests and I give them the best. That's the Italian style."

How did your career take off? "After I graduated from navy school, I was the first in my family to go to culinary school. Then I started travelling and each year worked with the best chefs around the world. In 2006, I opened Luigi Pomata, in Cagliari. I also started the first fusion restaurant in Sardinia, serving raw fish but in an Italian style, in the early 1990s. In Asia it's normal to have raw fish, but it's not in Italy. We treat tuna like a pig - we use everything - but cook it like beef. If you overcook it, it's too hard and doesn't have taste. At first they said, 'Why raw?' But then, when they tasted it, they realised it's so good. My signature dish is hand-cut red tuna tartare on buffalo mozzarella cream with micro cress. Another is tuna with foie gras, or tuna rossini."

Is that how you became known as the "king of tuna"? "I love everything about tuna - the skin, tripe, stomach; the eggs, like in a bottarga [salt-cured fish roe], with shrimp is fantastic. Tuna sperm is fantastic, like tofu. We boil then fry it and put it on a salad. It's very light."

What do you look for when you buy tuna? "I buy tuna in the best season - May - then freeze them to keep them in their prime. After June, when the eggs are released by the female tuna, it is not as good, not as fatty. I like canning the really fat tuna, which I then age for 20 years. The ones I pick weigh 100kg to 150kg."

Aren't you worried about sustainability? "We have to have sustainable food. When I eat on the mountain, I don't want to have salmon, I want to have pig. Why have tuna in the mountain? I want local food. But now fishermen catch too much tuna and there's a problem with small fish like sardines, anchovies and mackerel. We have to preserve tuna by fishing in moderation. In Sardinia, they fish for tuna for one month. The fishing vessels catch in one day what fishermen in Sardinia catch in a month. And they don't just catch tuna, but dolphins, sharks …"

How did you become a television chef? "Some producers were looking for a chef for the first Italian culinary show, which ran for eight years. Being on TV is very different from cooking in a restaurant. When I'm on TV, I cook two, maybe three dishes and it's all kinds of Italian dishes, not just tuna. I like being on TV because it's a way to communicate."

What do you do when you're not cooking? "I travel around the world, catering for events. I play basketball and do extreme mountain biking. My son is 11 years old. I think he knows how to cook - he has good taste. We cook together. He wanted to come with me to Hong Kong because he doesn't like school!"

Is he going to be a chef, too? "I hope so, if he likes it. My job is tough but there are good things about it. Every day you are out of the house, Saturday and Sunday everyone else is off and you have to work, but there is a lot that's special, if you do it with passion. In Italy, I'm famous but sometimes you have to work, attend events, cook for events. But I love my job."

Any words of wisdom for us? "If you make good spaghetti al dente with olive oil that's not too strong and 36-month parmesan, you can be a chef. The kitchen is sacred. It's magic."

Bernice Chan