Ingredients:
4 large onions, sliced
2 tablespoons butter
1 teaspoon sugar
2 quarts beef broth, no sodium added
¼ cup sherry
2 sprigs fresh thyme
1½ teaspoons salt
Pepper to taste
Sliced bread of choice (or croutons)
8 ounces Gruyere cheese, sliced (can substitute with Swiss)
Instructions:
Place onions, butter, sugar, and salt in the bottom of a 6-quart slow cooker. Cover and cook on high for 7 hours or until onions are soft and brown.
Add beef broth, sherry, thyme sprigs, and pepper to taste. Cover and cook on high for another hour.
To serve, arrange sliced bread (or croutons) across the surface of the soup. Top with sliced Gruyere cheese and serve.