Allegra McEvedy: The chef talks teenage grief, working for Robert De Niro and four-course family breakfasts

I must have seen every outpost of the Roman Empire by the time I was 11 My father was a psychiatrist and historian, so while I was growing up, and my friends were going on beach holidays like everybody else, we were visiting cathedrals, art galleries, all sorts of ruins. If it was Wednesday, it was probably Belgium.

Everything went tits-up for me at 16 I tried to thrive at school – and, for a while, I did. I attended St Paul's, in London, where everyone was on a fast-track to Oxford, Cambridge, and then into politics, or editing newspapers. I was a big, confident girl, captain of my prep school, liked by everybody, and it was all going swimmingly… then my mum got sick, I found out I was gay, and, shortly after my first moment with a lovely lady, Mum died.

I became self-destructive Teachers would complain that I hadn't done my French homework, and I had to remind them that my mum had just died, so what the hell did French homework have to do with anything? I was in a huge amount of pain. I behaved badly and the school didn't know what to do with me, so they expelled me.

Understanding takes time Much later, I was invited by the school's Lesbian and Gay Society to talk to the girls. Which was ironic, given that they couldn't handle me being gay in the first place. Never mind: progress!

Mum had wanted me to become a barrister The idea appealed for a while. I had the gift of the gab and a bit of Irish blood in me. But my heart was never in it. I think my dad realised it before I did.

Reinvention is tricky I moved to Manchester, where I became a pretty alarming proposition: 11 piercings in one ear, a buzzcut, a penchant for leather, very much enjoying Manchester's gay scene. Then my father took me to lunch on my 21st birthday; I remember sitting opposite him looking like every kind of nightmare daughter you could have.

You have to Know when to grow up Dad told me I had always liked cooking, so why not do a cookery course, and open a restaurant? So I got into kitchens, and in time became a chef. Twenty-two years later, I'm one still.

One day I realised I didn't want to do posh food for posh people any more I was working at Robert De Niro's restaurant, Tribeca Grill in New York, where we were charging $26 for a Chilean sea bass. I knew what the food cost, the mark-up, and I realised I didn't want to do it any more. I wanted to do the best food for the most people. So I came back to London, hooked up with my friend Henry Dimbleby, and we started Leon: making good food a little bit better, and available to all.

breakfasts are the most important meal in our house We like to give the kids four courses: melon and pineapple, pinhead porridge with brown sugar, waffle with maple syrup, then a yoghurt. Food shouldn't just be about hoofing it down; it's about the experience, spending quality time with family.

I've seen what a difference buying Fairtrade makes I've been working with Fairtrade for 10 years. I've visited Malawi and South Africa, and I've been able to see the difference it makes not just to those within the programme, but everyone within the community. People question whether it works. All I can say is: yes it does. It's life-changing.

Chef Allegra McEvedy, 44, who lives with the food writer Jack Monroe and their two children, runs the restaurant Blackfoot in London's Exmouth Market. She is a patron of Fairtrade, whose Fairtrade Fortnight runs from tomorrow to 8 March (fairtrade.org.uk/fortnight)