Ingredients
8 medium onions, sliced5 tablespoons butter, divided2 tablespoons all-purpose flourDash pepper3/4 cup beef broth1/4 cup sherry or additional beef broth1-1/2 cups salad croutons1/2 cup shredded Swiss cheese3 tablespoons grated Parmesan cheese
Preparation
In a large cast-iron or other ovenproof skillet, saute onions in 3 tablespoons butter until tender. Stir in flour and pepper until blended; gradually add broth and sherry. Bring to a boil; cook and stir until thickened, about 2 minutes.
In a microwave, melt remaining butter. Add croutons; toss to coat. Spoon over onion mixture. Sprinkle with cheeses.
Broil 3-4 in. from the heat until cheese is melted, 1-2 minutes.
