Heat the oven to 180C/160C fan/ gas 4 and butter an ovenproof baking dish (ours was 4cm deep). Cook the rice in a pan of lightly salted boiling water for 12 mins until tender, then drain and tip into the base of the prepared dish.

Cook the carrots in a pan of boiling water for 10-12 mins until just tender, or tip into a heatproof bowl with a splash of water and microwave for 2-3 mins. (If you’re using canned or frozen carrots, you can skip this.) Mix the carrots with the leeks and spoon this over the rice, spreading it out to cover.

To prepare the fish, remove the skin and any pin bones, then cut it into pieces. Arrange the fish over the vegetables, then scatter over the prawns.

Mix the egg yolks, mayo, crème fraîche and cheese together, and season.

Tip the egg whites into a clean bowl and beat with an electric whisk to stiff peaks. Gently fold the whipped egg whites into the mayonnaise mixture, then spoon this over the layer of fish and prawns in the dish. Spread it out with a spatula or the back of the spoon so it completely covers the fish. Bake for 20-25 mins, or until the topping is lightly golden brown. Leave to stand for a few minutes, then serve straight from the dish.