French Onion Soup
["1 1/2 lb. sliced onions (5 c.)", "1/4 c. butter", "6 c. beef or vegetable stock", "croutons", "Mozzarella cheese"]
["Peel and slice onions.", "Heat large soup pot.", "Melt butter and onion and cook over very low heat until light brown in color (15 to 20 minutes).", "Add stock; cover and simmer for 20 to 30 minutes. Season to taste with salt and pepper.", "Pour into oven safe soup bowls.", "Sprinkle with croutons and cheese.", "Broil to melt cheese."]
["onions", "butter", "beef", "croutons", "Mozzarella cheese"]