Prepare meat: Finely slice heart and liver, cut the rest of the meat into thin strips. Peel onion, chop finely. Melt butter, sauteé onions until slightly brown. Wash and clean yellow carrot, parsley root, celery, grate coarsely and sauteé briefly with the onion. Quench with a large dash of vinegar. Add heart and midriff, and some soup and simmer together with the seasonings and herbs for about one hour. Add liver, spleen and sweetbread last. Let the liquid boil down, dust with flour, mix thoroughly. Mix the blood with some vinegar and water, add red wine and beef stock and boil down until it becomes a thick sauce. Season with salt, pepper and parsley.