Cut open the flounder down the back. Dig inside under bone to right and left, without breaking the meat. Chop the bay leaves, thyme and clove of garlic very, very fine and mix with a half teaspoonful salt and a half teaspoonful of black pepper and a dash of Cayenne. Rub the Flounder all over the inside and under the cutting and outside with this preparation, seasoning thoroughly. Chop the shallots, green and white, very fine. Put a tablespoonful of butter in a flat saucepan or stewing dish, and put the shallots with the butter. Lay the Flounder on top of the shallots and butter, and let it cook slowly on a slow fire for about ten minutes. Then turn on the other side and cook ten minutes longer. In the meantime take another saucepan and put into it one tablespoonful of butter and two of flour. Dissolve this immediately with two cups of Bouillon or water so that the sauce will be white. Let it cook about five minutes, and then add the well-beaten yolks of the eggs and one can of mushrooms. Let all cook ten minutes longer, and then take the Flounder out of the saucepan in which it has been cooking and lay on a flat silver dish. Then mix the cooked sauce with the mushroom sauce. Taste the sauce and add salt, pepper and Cayenne, according to taste. Pour this sauce over the Fish, around which you will have placed Croutons cut as dice and fried in butter. Cover the Fish and put it in the bake oven for fifteen minutes. Serve hot in the dish in which it was baked.