BLACKFISH À L'AMERICAINE

Draw two large blackfish, trim, and clean thoroughly. Put into a baking-dish with two chopped onions fried in butter. Add two cupfuls of cold water and half a cupful of Port wine. Season with salt and pepper, a pinch of powdered cloves, mace, allspice, and thyme, two bay-leaves, a small bunch of parsley, and two leeks. Cover tightly and cook for an hour. Lift out the fish and strain the liquid. Thicken it with a tablespoonful of butter, blended with an equal quantity of flour. Bring to the boil, add two tablespoonfuls of butter, and minced parsley and lemon-juice to season. Pour over the fish and serve.