Court Bouillon, which means 'short boil', is a French soup/stew normally made with firm, white fish, but many other kinds of fish may be used as well. I like to use flat fish fillets like catfish, sole, flounder, tuna, snapper and perch. Of course, the type of fish you use will determine the flavor of the dish. I've included two methods of preparation for this recipe. I often use perch and tuna together as in the first method, because the perch falls to pieces and thickens the soup and the tuna maintains its shape. Note: Sometimes I make a fish stock first from fish heads and bones I can get from the fish monger. This must be strained well through cheesecloth as your stock. Or, you may prefer a vegetable stock. You may also like the rich flavor of a roux, and I've given instructions for that in the traditional method.