1 can (10-1/2 ounces) condensed beef consomme, undiluted
1/4 cup sherry, optional
4 slices French bread (1 inch thick)
1 cup shredded Swiss cheese
1/4 cup shredded Parmesan cheese
In a large skillet, saute onions in 2 tablespoons butter until tender. Sprinkle with flour; stir in salt and pepper. Add the consomme and sherry if desired; cook and stir until thickened, about 3 minutes.
Pour into a shallow 2-qt. baking dish or individual baking dishes. Spread remaining butter on both sides of bread; place on a baking sheet.
Bake at 350° for 10-15 minutes or until golden brown. Place bread on top of onion mixture; sprinkle with cheeses. Bake, uncovered, for 10-15 minutes or until cheese is melted and bubbly.