Bennigan's Onion Soup

1/2 pound firm white onions -- sliced
1/4 cup butter
2 tablespoons corn oil
3 tablespoons flour
1 quart chicken broth
1 quart beef broth
8 slices French bread
Shredded Swiss cheese -- as needed
Freshly-grated Parmesan cheese -- as needed

Sauté onions in butter and oil until onions are transparent, but not well
browned. When tender, turn heat to lowest point and sprinkle with flour,
stirring vigorously.

Pour into Dutch oven and stir in broths. Heat thoroughly and divide among
8 oven-proof bowls. Float a slice of bread atop each serving. Mix equal
parts of each cheese to smooth paste and spread over bread. Place all
bowls on oven rack 4 inches from broiler heat and broil until cheese
melts. Serve at once. Leftover soup freezes well up to 6 months.

Yields:  8 servings