Fish Pie with Potato and Spring Onion Mash

2. While the potatoes are cooking, lay the fish in a large frying pan and pour over the milk. Cover with a lid or baking sheet and bring slowly to the boil. Simmer gently for 5-7 minutes or until the fish flakes apart. Remove to a plate, peel away the skin and pull out any bones. Pass the milk through a sieve into a jug.

3. Melt the butter in a saucepan and add the flour, stirring for 2 minutes. Draw off the heat and slowly add the strained milk, stirring continuously. Return to the heat and simmer until the mixture thickens. Add the parsley, nutmeg (if using), the lemon juice, salt and pepper.

4. Once the potatoes are ready, discard the water from the pan underneath then pour in the milk to warm through. Add the potatoes and butter and mash with a potato masher until smooth. For a really smooth and lump-free mash, use a potato ricer and stir through the warm milk and butter. Season with salt and pepper and set aside.

5. Preheat the oven to 190C/375F/gas mark 5. Tip the fish into a pie or baking dish, keeping the flakes fairly large. Pour over the sauce and fold gently to combine. Spoon over the potatoes and spring onion and smooth the top. Bake for 25 minutes or until the potatoes are beginning to turn golden and the fish filling is hot and bubbling.