Onion Soup - cooking recipe

Ingredients

1/2 c. butter
4 large onions or 8 medium, sliced thin
1 1/2 Tbsp. flour
1 Tbsp. Dijon or other dark mustard
10 c. beef broth or 9 bouillon cubes, plus 10 c. water
black pepper to taste
salt to taste
Swiss cheese
slices of bread

Preparation

Slice onions and saute until light brown.
Add flour, mustard and seasonings carefully.
Add water or broth and simmer for at least 3 hours or more.