Kraut and Rib Soup

Cook ribs in a deep 6 to 8-quart pan over medium-high heat, turning as needed, until browned on all sides, about 25 minutes. Remove ribs from pan; set aside. Add vinegar to pan and stir to scrape browned bits free. Add oil, onion, caraway seeds, and bay leaves. Cook, stirring, until onion is translucent, about 3 minutes. Stir in sauerkraut, cabbage, barley and tomatoes with their juice. Return ribs to pan. Pour in broth. Bring to a boil over high heat; then reduce heat, cover, and simmer until meat pulls easily from bones, about 2 1/2 to 3 hours. Skim and discard fat from soup. If made ahead, let cool; then cover and refrigerate for up to 3 days. Reheat before serving. To serve, ladle soup into bowls.