Saute onion in oil for 10 minutes. Add meat and saute for 5 minutes. Add broth and simmer for 1 hour. Add potatoes, salt, pepper and bay leaves. Simmer for 20 minutes. Remove 1/2 cup broth from the soup and slowly stir in the flour, add the flour mixture to the soup. Simmer for 3 minutes. Add vinegar, cream and parsley. Stir, remove from heat and serve.