Hungarian Bean Soup (Bab Leves)

Name: Hungarian Bean Soup (Bab Leves)
Prep time: 20 min
Cook time: 3 h 30 min
Total time: 3 h 50 min
Cuisine: Eastern European
Ingredients: 1/2 pound navy beans ( dried ); 1/4 teaspoon ground pepper; 1 large carrot (peeled and sliced); 1 medium onion ( finely chopped ); 2 garlic cloves (finely chopped); 1 large bay leaf; 1 ham bone (or smoked ham hock ); 4 cups smoked ham stock (or ham base or chicken stock or water); 2 tablespoons butter; 2 tablespoons onion (finely chopped); 1 teaspoon paprika (mild or hot Hungarian); 3 tablespoons flour (all-purpose); 1 tablespoon parsley (fresh, chopped); 1/4 cup sour cream; 1 teaspoon vinegar