Cook duck or pork neck bones in salted water until done. Debone and put meat in soup. Add prunes, raisins and peaches and let boil.
Prepare blood: Use 2 cups for very large pot of soup. Mix with 1/4 cup of water in a large mixing bowl. Mix flour and blood slowly with hand mixer. Add enough flour to the mixture until it gets thick, like whipping cream. Slowly add this mixture to soup. Salt to taste. Add sugar and marjoram. Allow to boil and cool. Add cream or half and half slowly and then vinegar to taste. Serve with kluski thick noodles.