Scandinavian-style fish pie

Preheat your oven to 200°C (180°C) gas mark 6. Bring the new potatoes to the boil in a large pan of salted water. Cook until tender, 15-18 minutes.

Meanwhile, melt 30g of the butter in a large frying pan over medium high heat. Add the leeks and cook, stirring occasionally, until softened, 6-8 minutes. Stir through the flour and cook for a further minute then gradually stir in the stock until smooth. Add the sour cream and nutmeg, season with salt and pepper and bring to a simmer and cook until thickened, 2-3 minutes.

Stir the spinach through the leek mixture until wilted then remove from the heat. Add the salmon, haddock, prawns, dill and lemon zest and mix well. Transfer to the base of a roughly 2 litre baking dish.

Once the potatoes are cooked, drain them and return to the pan with the remaining 50g butter and season with salt and pepper. Roughly crush with the back of a wooden spoon so that the potatoes are broken up but still chunky.

Top the fish mixture with the crushed potatoes and transfer to a baking dish. Bake for 40-45 minutes until golden brown, crispy and bubbling. Leave to cool for 10 minutes before serving.