- 6 tablespoons olive oil
- 4 medium yellow onions, sliced 1/4 inch thick
- 1 tablespoon unsalted butter
- 1 clove garlic, thinly sliced
- 4 sprigs fresh thyme
- 1 bay leaf
- salt to taste
- 1/4 teaspoon ground white pepper
- 3/4 cup dry white wine
- 2 quarts chicken stock
- 1/2 cup port wine
- 6 slices French bread
- 2 cups shredded Gruyere cheese
- Heat the olive oil in a heavy pot over medium heat. Add the onions; cook and stir until golden brown, about 30 minutes.
- Add butter, garlic, thyme, bay leaf, salt, and white pepper. Cook and stir for about 10 minutes. Increase the heat to high, and stir in the white wine. Bring to a boil, and cook until wine has reduced by half, 3 to 5 minutes. Pour in the chicken stock, and simmer over medium heat for 45 minutes.
- Preheat the oven's broiler. Remove the thyme sprigs and bay leaf from the soup, and stir in the port wine. Ladle soup into 6 crocks or heat proof bowls, top each with a slice of bread, and a generous helping of Gruyere cheese. Place the bowls on a baking sheet for ease in handling.
- Place under the broiler for 2 to 3 minutes, until the bread and cheese are toasted and bubbly. Serve immediately.