Mode.--Detach the brains from the heads without breaking them, and put them into a pan of warm water; remove the skin, and let them remain for two hours. Have ready a saucepan of boiling water, add a little vinegar and salt, and put in the brains. When they are quite firm, take them out and put them into very cold water. Place 2 or 3 slices of bacon in a stewpan, put in the brains, the onion stuck with 2 cloves, the parsley, and a good seasoning of pepper and salt; cover with stock, or weak broth, and boil them gently for about 25 minutes. Have ready some croûtons; arrange these in the dish alternately with the brains, and cover with a matelote sauce to which has been added the above proportion of lemon-juice.