French Onion Soup - cooking recipe

Ingredients

6 c. (1 1/2 lb.) onions, thinly sliced
1/4 c. butter or margarine
3 (10 1/2 oz.) cans condensed beef broth
1 tsp. Worcestershire sauce
1/4 tsp. salt
6 to 8 slices French bread (toasted)
6 to 8 slices Swiss cheese
grated Parmesan cheese

Preparation

In a covered 3 quart saucepan cook sliced onions in butter until tender, about 20 minutes.
Add beef broth, Worcestershire sauce, salt and dash of pepper.
Bring to boiling.