BAKE: Line the baking pan with foil for easier removal of the baked fish, which may stick to the pan, or use a nonstick pan. Bake fish in a preheated 400 °F to 450 ° F oven. Place the fish on a large square of cooking parchment or foil, fold the wrapping over the contents, crimp the edges together to seal it, and bake until the fish tests done.
BROIL/ GRILL: Whether grilling or broiling, position the rack so the fish is four to six inches from the heat source. Give any grill or broiler rack a liberal coating of nonstick cooking spray before grilling fish, and preheat it before placing the fish on it. You can also grill fish on top of a perforated sheet of foil in a covered barbecue.
POACH: Fish steaks, fillets, or whole fish can be poached by immersing the fish in a pan of simmering fish stock, a mixture of water and lemon juice or wine, or water and skim milk. Bring the liquid to a gentle simmer, partially cover the pan, and poach until the fish is opaque. Or, place the fish in already-simmering liquid and continue as described.
SAUTE: Use a nonstick pan liberally sprayed with cooking spray or brushed with oil; heat the pan, then add the fish. Cook, turning once (turn carefully to avoid breaking the fish) until the fish is lightly browned on the outside and it tests done on the inside. Remove the fish from the pan promptly.
STEAM: Any fish that can be poached, whether whole, steak, or fillet, is also a candidate for steaming--and since the fish is not immersed in cooking liquid, it retains more of its natural flavor. You can use a vegetable steamer, a heatproof plate atop a steaming rack in a pot or skillet, or a wooden Chinese steamer that can be placed in a wok or large skillet. Use 1" to 2 " of water as the cooking liquid, to which you can add fresh herbs such as fennel or dill. Bring the water to a boil, place the fish in the steaming basket (or on the steaming rack), cover the pot tightly, and steam the fish until it tests done.