6 lg. yellow onions, thinly sliced
2 tbsp. butter
1 tbsp. olive oil
6 c. freshly made or canned beef broth, or bouillon
Salt & pepper to taste
1/3 c. white or red port wine (opt.)
1/2 c. diced Gruyere cheese
6 slices buttered, dry toasted French bread, sliced about 1/2" thick
1 c. mixed shredded Gruyere & Parmesan cheese
1 tbsp. melted butter

Using a heavy 3 or 4 quart covered pan, saute onions in butter and oil until limp. Cover and let simmer slowly for 15 minutes. Stir in beef broth or bouillon, adding salt and pepper to taste, and wine if desired. Pour into ovenware casserole, cover and heat in a moderate oven, 350 degrees for 30 minutes.

Remove from oven and sprinkle with the diced Gruyere cheese. Cover with an even layer of toasted French bread and sprinkle with the shredded cheeses. Dribble over the melted butter. Return to a hot oven, 450 degrees for 10 minutes, then turn on the broiler and heat just until the cheese browns lightly on top. Makes 6 servings. If individual soup bowls are used for heating, reduce times by about one half.