Preparation time: 45 minutes
Cooking time: 30 minutes
* 625g (1lb) potatoes, peeled and cut into chunks
* salt and freshly ground black pepper
* 1 litre, plus 4 tbsp hot milk
* 150g butter, plus extra for greasing
* 10 black peppercorns
* 2 bay leaves
* 1 small onion, quartered
* 750g skinned haddock fillets, cut across into pieces
* 60g plain flour
* 5–7 sprigs of flat-leaf parsley, leaves picked and chopped
* 125g cooked, peeled prawns
* 3 eggs, hard-boiled and coarsely chopped
1. Cook the potatoes in boiling salted water for 15-20 minutes or until tender. Drain thoroughly, then mash with the four tablespoons of hot milk, 60g butter, and salt and pepper to taste. set aside.
2. Pour the remaining milk into a large saucepan and add the peppercorns, bay leaves, and onion. Bring to the boil, then remove from the heat. Cover and leave in a warm place to infuse for about 10 minutes.
3. Add the fish to the milk, cover, and simmer for five to 10 minutes, or until it will flake easily when tested with a fork. Use a slotted spoon to transfer the fish to a plate and reserve the cooking liquid. Cool, then flake the fish.
4. Melt the remaining butter in a saucepan over medium heat. Whisk in the flour and cook until foaming, then strain in the fish cooking liquid, still whisking. Cook, stirring constantly, until the sauce boils and thickens. Simmer for two minutes. Season and stir in the parsley.
5. Preheat the oven to 180°C (350°f/Gas 4). Ladle a third of the sauce into a buttered two litre pie dish.Spoon the flaked haddock on top in an even layer.
6. Cover with the remaining sauce, then scatter on the prawns and chopped hard boiled eggs. Spread the mashed potatoes on top to cover completely
7. Bake for 20-30 minutes or until the potato topping is tinged with brown and the sauce is bubbling up around the edge. Serve hot
Cook's tip:For best results, cut the potatoes into equal chunks so they cook evenly, and be sure they are tender before mashing with hot milk, butter, and seasoning. Then beat with a wooden spoon or hand-held electric mixer over medium heat for a few minutes until fluffy.
MasterChef Cookery Course, published by DK, £26, dk.com. Also available as an eBook to download from the iBookstore and Amazon Kindle Store.
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For more recipes from MasterChef Cookery course
*Hot cross buns recipe
*Chocolate fondant recipe