Infuse the milk by chopping the onion in half, and adding to a pan with the milk, bay leaf and cloves. Heat the milk until warm but do not allow to boil. Pass the milk through a sieve and set aside for later.
Place the fish and prawns on a lightly oiled baking tray and bake in the oven for 5 minutes at 180°C. Remove and set aside.
Trim and finely slice the leeks and wash well. Soften the leeks in half the butter and cook (without browning) for 5 minutes. Stir in the flour and mix well to form a roux. Slowly add the infused milk to make a thick rich sauce.
Stir the peas and baked fish mix into the sauce with the finely chopped parsley. Gently stir without breaking the fish.
Place in a deep casserole dish, cover and leave to cool.
Peel the potatoes and cut into 25mm chunks. Pop them in a pan, bring to the boil and simmer until cooked. Drain and mash with butter.
Top the cooled fish pie mix with mash, decorate with a fork. Cook for 25-30 mins at 180 degrees until golden brown.
