This is a classic British fish pie, a comforting dish featuring tender white fish and prawns in a creamy sauce, topped with fluffy mashed potatoes. It's a satisfying meal, perfect for any occasion.
Prepare the Potatoes: Place 900g of floury potatoes in a large pan. Cover them with cold, salted water. Bring the water to a boil over high heat. Reduce the heat to low. Cover the pan. Simmer gently for 15 minutes, until the potatoes are tender. Drain the potatoes completely. Return the drained potatoes to the pan over low heat for 30 seconds to remove any excess water. Mash the potatoes well. Add 1 tablespoon of olive oil to the mashed potatoes. Season with salt and pepper to taste. 2. Poach the Fish: Pour 600ml of semi-skimmed milk into a large sauté pan. Add 800g of white fish fillets to the milk. Bring the milk to a boil. Remove the pan from the heat. Cover the pan and let it stand for 3 minutes. Carefully remove the fish from the pan, reserving the milk in the pan for later. Pat the fish dry with kitchen paper. Gently flake the fish into an ovenproof dish. Discard any skin or bones from the fish. 3. Make the Sauce: Heat the remaining 1 tablespoon of olive oil in a separate pan. Stir in 1 tablespoon of plain flour. Cook for 30 seconds, stirring constantly. Gradually stir in 200-250ml of the reserved milk, stirring continuously to prevent lumps. Discard any remaining reserved milk. Grate fresh nutmeg into the sauce. Season the sauce with salt and pepper. Cook, stirring, until the sauce thickens and bubbles. Stir in 3 tablespoons of double cream. 4. Combine Ingredients and Prepare for Baking: Preheat your oven to 190°C (375°F) or 170°C fan (340°F) or Gas Mark 5. Grate 200g of Jerusalem artichokes. Add the grated artichokes, 1 finely sliced leek, 200g of peeled raw prawns, a large handful of chopped parsley, and a handful of chopped dill to the ovenproof dish with the flaked fish. Stir the grated zest of 1 lemon and the juice of 1 lemon into the prepared sauce. Pour the sauce over the fish and vegetable mixture in the dish. Gently mix all ingredients in the dish with a wooden spoon to combine. 5. Bake the Pie: Spoon the mashed potatoes evenly over the fish mixture. Use a fork to create peaks on the surface of the mashed potato layer. These peaks will crisp and brown during baking. Sprinkle 25g of grated Gruyère cheese over the mashed potatoes. Bake in the preheated oven for 35-40 minutes. The fish pie is ready when the topping is golden and bubbling. Serve hot with wilted greens.