The three secrets to success...
Don't overcook fish as the texture will coarsen, dry out and the flavour will be destroyed.
Don't
overspice fish as it has very delicate flavours so be light-handed with herbs and spices.
Keep fish moist and preserve the natural juices whilst cooking by using a moist cooking method or baste frequently during dry cooking.
Cooking Methods:
Baking
Baking in a moderate oven 180-200C (350-400F) is an extremely useful method of cooking whole fish, fillets, cutlets or steaks. But remember it is a dry heat method and fish, especially without its skin, tends to dry out, so use a baste, marinade or sauce to reduce the moisture loss.
Baking in Foil
Baking in foil is an excellent way to retain flavour and moisture particularly of larger steaks, cutlets or whole fish. Use a liquid such as fish stock, white wine or lemon juice with a little butter, salt, pepper and seasonings of your choice before sealing the fish in foil. Bake in a moderate oven 180-200C (350-400F) for a mouth-watering result.
Barbecuing
Barbecue fish, but protect it with marinades, bastes, lemon juice or oil or butter brushed on frequently during the cooking. Or wrap it in foil with these liquids and seasonings. Be careful turning the fish over during cooking.
Casseroling
Casseroling in a little liquid in a covered dish in a moderate oven will achieve a dish in which the subtle differences in the flavours of the various species and their natural juices are maintained.
Shallow Frying
Shallow frying is cooking in a small quantity of fat sufficient to come up to the level of half the thickness of the fish - in a wide shallow pan. The best fat for fish is butter or half butter and half olive oil. The oil combined with the butter reduces the risk of overheating the butter.
Deep Frying
Deep frying
is immersing the fillet or whole fish in deep oil in a deep pan after protecting it first with a coating such as egg and breadcrumbs or batter. The oil must be at the correct temperature (175-195C) before placing the fish into it. If the oil isn't hot enough the coating will soak up the oil and become greasy and if it is too hot the coating will burn before the fish is cooked. To test the temperature without a thermometer the oil should be heated until a faint haze rises from it before dropping a small cube of bread into it. If it rises, bubbling to the surface and becomes golden brown it is ready. If it turns dark brown rapidly the heat must be reduced and if it sinks and stays low in the oil it is not hot enough yet.
Oven Frying
The result is similar to shallow frying but is done in hot butter in a preheated baking dish in a hot oven 230-250C (450-500F). Because of the high temperature used the fish cooks quickly so this method is best suited to thin whole fish.
Grilling
Grilling (or broiling as Americans sometimes call it) is a fast way to cook fish. Using either fillets or whole fish this simple method allows the fish to develop its own rich flavour under the intense heat. Fish should be basted during cooking, either with butter or oil or a prepared baste, to prevent it drying out. Alternatively the fish may be marinated beforehand and the liquid used for basting. Whole fish or thicker fillets seem to fare better under the grill as the fish has time to develop a rich golden brown by the time the inside is cooked. The high heat penetrates and cooks thin uncoated pieces too fast for browning to occur. If whole fish are to be grilled score the skin and flesh to allow better heat penetration.
Marinating
Marinating
has two distinct purposes: the first is to impart a flavour by presoaking the fish in a mixture of lemon juice, oils and flavourings and then using the marinade liquid to baste during grilling, barbecuing or baking. The second is to replace the cooking process altogether. Very fresh fish is cut into boneless bite sized pieces and left to soak in lemon juice and other flavourings until the flesh becomes opaque and white right through - approximately 6 to 12 hours in the refrigerator or 4 to 8 hours at room temperature. The marinade is then strained off and the fish added to crisp, finely cut vegetables with dressings or sauces such as mayonnaise, yogurt or coconut cream. It is then served chilled.
Poaching
Poaching as far as the fish is concerned means totally immersing it in seasoned stock or court bouillon. The liquid should be brought rapidly to the point where the surface begins to swirl but with no bubbles rising to surface (boiling should not occur). At this point the heat should be reduced (and sometimes even turned off). Inspect to see if the flesh flakes easily and comes away from the bone. Poaching is unmatched as versatile method of cooking fillets, steaks, cutlets or whole fish of any fleshy type. It can then be served steaming hot, dressed in a sauce made from the poaching liquid or chilled and served in a variety of salads or as a cold entree. It's the perfect cooking method for weightwatchers!
Sousing
Sousing is gently cooking small fish or fillets in a combination of vinegar, water and a selection of various herbs and spices. Although it may be served either hot or cold, the delightful delicate piquancy of the subtle blend of flavours only becomes evident after chilling. Fish cooked this way will keep for up to a week in the refrigerator.
Steaming
There are two types of steaming. In one the fish is put into the upper part of a double saucepan with a perforated base and a tightly fitted lid. Steam rising from boiling water in the saucepan below, passes through the perforations and surrounds the fish cooking it. In the second type of steaming no steam reaches the fish as the upper part of the saucepan has no perforations (two plates on top of the saucepan can be used if no double saucepan is available.) This method is slower than the first but effective and retains all the natural juices.
Microwave Cooking
Seafood adapts well to microwave cooking - natural flavours and colours are retained and often enhanced by this quick method of cooking. The seafood can be cooked without any additional liquid other than perhaps a small amount of melted butter, lemon juice or wine. Covering fish with tomatoes, lemon or orange slices or herbs will help to retain moisture and enhance the flavour. Grilling and frying fish is possible if a browning dish is used.
To test when fish is cooked...
Test the fish at the thickest part by prodding it with a fork. The flesh should "flake" readily. Another indication is when the inside flesh turns from translucent to white. Don't be tempted to "give it a moment or two longer" as it is very easy to overcook fish.