This is Martha's favorite cold-weather soup. The onions cook for 2 hours in butter and oil to develop the rich golden color of the perfect onion soup. It helps if you have homemade beef or veal stock on hand. This recipe comes from "Entertaining," by Martha Stewart.
- 5 pounds yellow onions, thinly sliced
- 6 tablespoons butter
- 2 tablespoons olive oil
- 1/2 teaspoon sugar
- 2 teaspoons salt
- 5 tablespoons flour
- 14 cups boiling beef or veal stock
- 1 1/2 cups dry vermouth or dry white wine
- 1/3 cup cognac
- 2 French baguettes, sliced 1 inch thick
- 4 cups coarsely grated Swiss and Parmesan cheeses, mixed
Simmer the onions in butter and oil for 2 hours. Stir frequently, adding the sugar and salt after 15 minutes of cooking. Onions will turn a deep golden-brown color. Sprinkle on the flour and cook for 5 minutes longer. Add the boiling stock and the wine and simmer for 45 minutes longer. Skim if necessary. Correct the seasoning.
Before serving, reheat to boiling. Pour in the cognac. Serve in heated bowls with toasted rounds of French bread and generous servings of coarsely grated Swiss and Parmesan cheeses.