Adapted from
The Joy of Cooking (2006 edition) by Irma S. Rombauer, Marion Rombauer Becker, and Ethan Becker...
One of the most enjoyable aspects of making this recipe is drinking all but 2 Tbs of the sherry along the way.
Heat in a soup pot over medium-low heat until the butter is melted:
- 2 Tbs butter
- 2 Tbs olive oil
- Add and stir to coat:
- 5 medium onions, thinly sliced
- Pinch of dried thyme
Cook over medium heat, stirring occasionally and keeping and eye on the onions so they do not scorch. As soon as they start to brown, about 15 minutes, reduce the heat to medium-low and continue to cook, covered, stirring, until they are a rich brown, about 40 minutes. Stir in:
- 2 Tbs dry sherry or Congac
Increase the heat to high and cook, stirring constantly, until the sherry has evaporated. Stir in:
Bring to a boil, reduce the heat, and simmer, partially covered, for 20 minutes. Season with:
- 1 tsp salt, or to taste
- 1/4 tsp black pepper, or to taste
Place 4 ovenproof soup bowls or crocks on a baking sheet.
Ladle the hot soup into the bowls and top each with:
- 1 to 3 slices French bread, toasted (8 to 24 slices, total)
Cover each bowl with:
- Gruyere or Swiss cheese, sliced about 1/8" thin
Broil until the cheese is melted and brown.