In a Dutch oven, bring potatoes, water and salt to a boil over med-high heat. Cook until tender, about 10 mins. Add Kielbasa, kraut, and onion. Return to a boil; cook for an additional 10 mins. In a small bowl, combine s.crm, and flour; gradually stir in one cup of hot soup mixture. Stir s.crm. mixture into the soup;blend well. Heat through withut boiling.. If desired, add pepper to individual bowls. Makes 4 servings.