My recipe for French Onion Soup

I love, love, love, French Onion Soup.  It was such a staple of my youth in the winter.  Once or twice a year my mother would start slicing mounds of onions and soon enough the whole house would fill with the wonderful scent of sauteing down to a mound of caramelized onions with wonderful beef broth, crisp french bread and bubbling Gruyere cheese.  Over the last few years I have developed my own recipe based on the recipe found in the Joy of Cooking and Martha Stewart's Cooking School, Lessons and Recipes for the Home Cook.  One of the nicest things about this recipe is that it is uber easy to make, but it is also easy to freeze and have on the cold dark nights of winter (I usually double it).

Ingredients:
6 tablespoons unsalted butter
3 pounds of onions, peeled and sliced (about 6)
6 cloves of garlic, sliced
1 teaspoon sugar
1 teaspoon all purpose flour
7 cups beef stock (I use the store bought organic, low sodium, but homemade is always better :) )
3 tablespoons cognac (If I have it, I use it.  If not I leave it out)
1/2 cup of dry white wine
1 teaspoon Dijon mustard
slices of baguette or crusty bread
6 ounces (or more) Gruyere cheese, grated

Caramelizing Onions:
Melt butter in a heavy large pot over medium heat (I tend to use a le Creuset and end up having to use two as there are so many onions). Add onions and garlic and sprinkle with sugar.  The pot will be very full (nearly overflowing, but the onions will reduce as they cook).  Cook the onions, stirring occasionally to prevent sticking, until onions are very tender and brown, about 45-60 minutes.

Making the Soup:
Sprinkle flour over the onions and stir to combine.  Add wine and cognac and bring to a simmer for 2-3 minutes.  Stir in beef stock and mustard, partially cover the pot and let simmer for 20-25 minutes.  Season to taste with salt and pepper. (At this point you can freeze the soup now if you want to).

Putting it all together:
Preheat broiler.  I like to lay my slices of baguette out on a baking sheet and lightly toast them for 2-4 minutes under the broiler.  Flip them over when they are half way through. Ladle the soup into ovenproof bowls.  Top each bowl with a slice of french baguette and then a handful of cheese.  Broil until cheese melts and is bubbly. Enjoy.