French Onion Soup

1. 1/2 stick (1/4 cup) butter 
2. 2 pounds yellow onions, cut into slivers (about 6 cups)
3. 2 teaspoons sugar
4. 1 heaping tablespoon flour
5. 3 1/2 cups beef stock, boiling
6. 2 cups water
7. 1/4 cup cognac
8. 1 1/2 teaspoons salt
9. 1/2 teaspoon ground black pepper
10. 12 slices stale French bread (each about 3/4 inch thick)
11. 1 1/2 pounds Gruyère or Emmenthaler (Swiss cheese), coarsely grated 

1. Melt butter over moderate heat in large saucepan. Add onions and sugar, stir well, and cover. Cook, stirring occasionally, for about 20 minutes, or until onions are wilted and light golden. Uncover and continue to cook for another 20 to 25 minutes, or until onions are brown and well caramelized.
(Watch carefully, so the onions don't burn.)

2. Add flour to pan, stir well to incorporate flour into onion mixture, and slowly stir in boiling stock, water,
3 tablespoons of cognac, salt, and pepper. Boil for 5 minutes, then reduce heat to low, and simmer gently, partially covered, for 45 minutes. Uncover and simmer for another 10 minutes. Adjust seasoning and add the remaining tablespoon of cognac.

3. While the soup is simmering, in a preheated 400 degrees oven, toast the bread slices for 10 minutes, turning them once after 5 minutes (the croutons should be well toasted on each side).

4. Divide the soup among 4 ovenproof onion soup bowls (or any ovenproof soup bowls), each with a capacity of approximately 1 1/2 cups. Arrange the croutons on top of soup (try to make an even layer of croutons that tops each bowl). Sprinkle croutons generously with grated cheese, allowing some cheese to spill over onto the rim. Put bowls on a cookie sheet and place under a preheated broiler until cheese melts and forms a crust over the tops of the bowls. Serve immediately.

Note: Instead of grating all the cheese, you can cut some of it into wide, thin slices and drape the slices over the sides of the bowls. This helps to prevent the cheese from slipping off the rims of the bowls.