Here is the recipe for the soup
as posted by "gourmetphobe" on the epi forum. I use more than the 5 cups of onions called for-they cook down to almost nothing. I also saw on Julia's DVD that she grated a little raw onion into the pot right before serving--I forgot to try that. I'll post the stock a little later.
JULIA'S SOUPE A L'OIGNON--the classic version (6-8 servings)
From Mastering the Art of French Cook, Volume One
3 Tablespoons butter
1 Tablespoon olive oil
5 cups thinly sliced yellow onions
1 teaspoon salt
1/4 teaspoon sugar (to help carmelize the onions)
3 Tablespoons flour
8 cups light beef stock, at a boil
1/2 cup dry white wine (like extra dry vermouth)
Salt and pepper to taste
3 Tablespoons cognac
Garnish: 6-8 croutes of hard toasted French bread rounds; 1-2 cups grated Swiss or Parmesan cheese
Melt the butter and oil over low heat in a heavy soup pot. Stir in the onions, cover, and sweat til tender, about 15 minutes. Remove the cover, turn the heat up to medium, and stir in the salt and sugar. Cook 30-40 minutes, stirring often, until the onions have turned an even, deep, golden brown. Sprinkle in the flour and stir for 3 minutes.
Take the pot off the heat and whisk in the boiling stock. Add the wine. Season to taste. Put back on the heat, bring to a simmer, and simmer, partially covered, for 30-40 minutes or more, skimming as needed. Correct seasoning (you can set it aside uncovered at this point until you are ready to serve.
When ready to serve, with the soup at a simmer, stir in the cognac. Place the toast pieces in the bottoms of each bowl, pour the soup over it, and pass the cheese separately for your guests to help themselves.