Three Fish Pie

Get your oven going to 200°C/400°F/Gas 6 (or 180°C fan).

Place the potatoes in a saucepan, cover with cold salted water, and bring to a boil. Simmer until the potatoes are completely tender when pierced with a fork. Drain them thoroughly, then mash with a knob of butter and a dash of milk. Stir in some pepper, then taste and adjust the seasoning with salt and more pepper if needed.

To start the fish filling, melt 75g of butter in a saucepan. Add the sliced leeks and stir them over the heat. Cover the pan and let them simmer gently for about 10 minutes, or until they're soft and translucent. While the leeks cook, measure 75g of plain flour into a small bowl, then whisk in 150ml of white wine until you have a smooth paste.

Pour 568ml of milk into the softened leeks and bring it to a boil. Stir in the wine and flour mixture, whisking briskly until the sauce is thickened, enough to coat the back of a spoon. Season the sauce, then add the chopped parsley, salmon, haddock, and smoked haddock. Stir everything together over the heat for two minutes. Spoon this mixture into an ovenproof casserole dish, then scatter the 6 hard-boiled eggs over the top. Let it cool until the filling is firm.

Carefully spoon the mashed potatoes over the cooled fish filling, spreading it evenly. Use a fork to create some texture on top, then sprinkle with 50g of Gruyere cheese.

Bake the pie for 30–40 minutes, or until the potato topping is lightly golden-brown and the sauce is bubbling around the edges.