Fish can be cooked in many different ways. Of course, certain varieties are better suited to particular cooking techniques but let's assume you've just bought a piece of haddock. Below are a number of different ways you could cook it. You can tell if it's cooked as it will have lost the translucent appearance and the flesh should break easily into lovely flakes.
This is a simple technique that ensures the fish remains moist. Choose a pan that's a little bigger than the amount of fish you're cooking. Lay the fish fillets in the pan then just cover with milk. Add a few whole black peppercorns and a bay leaf, if you've got one. Bring to a simmer and cook for about 8-10 minutes, or until the fish is cooked through. Remove with a slotted spoon. Great served with mash and peas.
Refer to the instruction booklet for the precise timings for your make of steamer. Pop some new potatoes into one tray, fish fillets in another, and some fine French beans in a third and cook according to the instructions (adding the ingredients in the correct order so they're all ready at the same time!). Serve with a quick sauce made from melted butter, a dash of white wine and a touch of mustard.
Baking is a good option if you want to include some other flavours with the fish. Take a piece of foil large enough to wrap loosely around the amount of fish you're cooking. Place some thin slices of lemon on the foil. You could also add lemon grass and red chilli, if you like. Place the fish on top and drizzle over a little oil. Wrap the foil up and around the fish, leaving a small opening in the top, to allow steam to escape. Bake in a preheated oven at 200C/400F/Gas Mark 6 for about 18-20 minutes, depending on the size and thickness of the fish.
Lay some foil over the grill tray, place the fish on top and drizzle with a little oil and lemon juice. The cooking time will depend on the size of the fillets but keep checking the fish and turn halfway. You could also add a touch of flavour to your fish by spreading a teaspoon of green pesto on the top and scattering over some grated Parmesan a couple of minutes before the end of the cooking time.