Clean and wash the fish, rub with salt and black pepper and set aside on a platter. Chop one large onion fine. Take a large and deep kitchen pan; place in it a tablespoonful of butter, the chopped onion, bay leaf and thyme. Place the Fish on top of this and pour over it a half bottle of White Wine. Cover with another close pan and put the whole on top of the stove. Bake from the bottom. When it begins to boil from below, turn the Fish over carefully without breaking, and let it cook on the other side. Take a saucepan and put in it a tablespoonful of butter and mix thoroughly with two tablespoonfuls of flour. Let it brown without burning, and then add six fresh tomatoes skinned and chopped fine, or a pint can. Add two dozen Lake Shrimp that have been cleaned well and scalded, a half can of mushrooms, salt and pepper to taste. Let all cook for about five minutes and then water with the gravy in which fish is cooking. Mix well and cover the fish with it. Parboil one dozen Oysters, and when the Fish is cooked set it in the dish in which it is to be served and place the Oysters all around it on small slices of dry toast. Cover the Fish alternately with the Shrimp and Oysters, as a garnish over and around it. Mash two crackers until crumbs and sprinkle over and place alternately small bits of butter on top of the Fish. Place in the oven and bake the Fish with a quick fire until light brown, and serve immediately.