Fish Pie (Creamy Fish Pie with Mashed Potato Topping)

Instructions

1. Boil the potatoes in salted water for 15 to 20 minutes until tender. Drain, steam dry for 2 minutes, then mash with the butter, hot milk, nutmeg, salt and pepper until smooth.
2. Put the cod, smoked haddock and salmon in a wide pan with the milk, bay leaf, onion slice and peppercorns. Bring to a bare simmer, cover and poach for 4 to 5 minutes until just opaque. Lift the fish out with a slotted spoon and strain the milk into a jug.
3. Flake the fish into large chunks, discarding any bones, and put it in a 2.5 liter (10 cup) baking dish with the shrimp, peas and eggs.
4. Melt the butter in the clean pan, stir in the flour and cook for 1 minute. Add the warm poaching milk a ladle at a time, whisking, then simmer for 5 minutes until thick. Stir in the parsley, mustard and lemon juice and season, tasting first because smoked fish is salty.
5. Pour the sauce over the fish and fold gently to coat. Heat the oven to 200°C (400°F).
6. Spoon the mash over the filling, spread it to the edges and rough up the surface with a fork. Scatter over the cheese if using.
7. Bake for 30 minutes, until the top is golden, the sauce bubbles at the edges and the fish reaches at least 63°C (145°F). Rest for 5 minutes before serving.

Tips

• Use at least three kinds of fish: a firm white fish, a smoked fish and an oily one. A fishmonger's ready-mixed pie fish works well, and undyed smoked haddock tastes better than the bright yellow kind.
• Do not overcook the fish when poaching, since it cooks again in the oven. You can assemble the pie up to 24 hours ahead and chill it, adding about 10 minutes to the baking time.