French Onion Soup

1 stick butter
4 large yellow onions, thinly sliced
salt
5 cups meat stock/broth
2 bay leaves
freshly ground pepper

Melt butter over low heat. Add onions and sprinkle salt to taste. Stir to coat well with butter. Cover and cook, stirring occasionally, until very tender (20-30 minutes). Remove cover, raise heat slightly and saute onions, stirring frequently. Saute until onions turn a deep caramel brown (1 hour or more). Careful not to burn them! Add beef broth and bay leaves. Bring to a boil and reduce heat. Cover and simmer about 30 more minutes. Discard bay leaves. Add salt and pepper to taste. Serve hot. If you like, top soup with Gruyere or Swiss cheese.

Recipe from Williams & Sonoma "Soups" Cookbook