- 4 large onions
- 1/4 butter
- 1 tablespoon flour
- 6 s beef broth
- 1/2 to 1 teaspoon Tabasco sauce
- 6 slices French bread, toasted
- 6 tablespoons shredded Mozzarella cheese
Cook onions in butter until transparent. Add flour; blend well. Put in slow cooker. Add beef broth and Tabasco. Cook on low 7 to 9 hours or high 4 to 5 hours. Ladle soup into oven-proof bowls. Top each bowl of soup with a slice of bread and shredded Mozzarella cheese. Broil until cheese melts. Sprinkle individual servings with Parmesan cheese, or serve grated Parmesan on the side. Serves 6.