Catfish is widely used in a number of cuisines. Its firm, white flesh and delicate flavor are suited to a wide range of dishes, from the most intricate Asian preparations to the simplest down-home specialties of the American South. There, catfish is often fried in breadcrumbs or batter, or blackened in the Cajun manner. Another simple preparation is boiled catfish, though the term is a misnomer. The fish should be poached in gently simmering water for best results, rather than at a hard boil.
Fill a wide, shallow pan with water, wine or any other suitable cooking liquid. Season generously with salt and pepper, preferably freshly cracked peppercorns. Add any further flavoring ingredients you like, such as onions, a bay leaf or lemon slices.
Bring the mixture to a simmer. The water should be gently moving and producing an occasional bubble, but should not be boiling. If you are using any optional flavorings, allow them to simmer for at least 20 minutes to extract the flavors.
Slide the catfish fillets gently into the poaching liquid with the "pretty" side facing up and the side where the skin was facing down.
Simmer for 6 to 8 minutes, depending on the thickness of the fillets. Baste the top of the fillets regularly with the cooking liquid.
Remove the fillets from the pan when the flesh is just barely translucent at the thickest point. Drain well and serve hot, or reserve the cooked catfish for use in another recipe
Chefs often prepare a special poaching liquid called "court bouillon" ahead of time to impart flavors to the fish. Typical ingredients include onions, garlic, thyme, white wine or wine vinegar and various spices.
Fish can be poached in milk or cream for a mild, rich flavor.