French Onion Soup

1/4 cup butter or margarine
5 cups thinly sliced onions
1/4 tsp. sugar
1 cup red wine
4 cans (10-1/2 oz.) condensed beef broth, undiluted
4-6 French bread slices, each one inch thick
1 cup grated Swiss cheese
Olive oil

Preheat oven to 325 degrees. Melt butter in large soup pot. Add onions, stir, and simmer covered until golden, about 15 minutes, stirring occasionally. Uncover, raise heat to medium, and stir in sugar. Cook 10 minutes. Add red wine and beef broth, bring to boil. Reduce heat and simmer for 30 minutes. (Can freeze soup at this stage if desired). Meanwhile, toast bread slices until browned on both sides. Sprinkle each slice of bread with grated cheese and a few drops of olive oil on top. Pour soup into oven-proof tureens. Float toast, cheese side up, one slice in each bowl. Bake at 325 degrees for 20 minutes, then set for a minute under the broiler until the top is browned and bubbly. Serve immediately, or cool and refrigerate, covered. May be reheated.