The rabbit meat should be placed in a jar and covered with equal parts of vinegar and water. Add one large sliced onion, salt and pepper to taste, clove and bay leaf. Let the meat soak in this solution for 2 days, then remove the meat and brown in hot butter, turning it often. Gradually add some of the sauce in which the meat was pickled. Let simmer until meat is tender (about 30 minutes). Just before serving, stir 1 cup of thick sour cream into the sauce.