Sweetbread (Animelle) with Marsala wine

Once you have thoroughly cleaned the sweetbread, soak it in boiling water and rinse it in cold water, so that the surface film can come off easily. Brown the oil (lard or olive oil) in a pan with a full tbs. minced onion and thinly chopped ham; then add the sweetbread, salt and pepper. Cook everything on a low flame, and cover with a lid. When it is halfway cooked add the marsala, alternating it with hot water. The sweetbread must be cut into thin slices, following  to its  original forms. Separately, warm up the sauce left over from the cooking, and let it reduce. Add some butter and pour it on the sweetbread, which has been placed on a serving dish. Serve immediately.