Bacon Onion Soup


Preparation info

  • Difficulty


  • Serves


Appears in

The Bacon Bible

The Bacon Bible

By Peter Sherman and Stephanie Banyas

Published 2019

  • About

French onion soup is one of the first things you make in culinary school, and it is really only about two things: the onions and the stock. The key to perfectly caramelized onions is patience; they must be cooked very low and very slow. The bacon stock sets this soup apart from the classic veal stock versions and, dare I say, elevates it to new status. This recipe is close to the one I learned at the French Culinary Institute years ago, except for the addition of bacon, of course.


  • 4 tablespoons (55 g) unsalted butter
  • 4 large Spanish onions, halved and thinly sliced
  • 1 cup (240 ml) dry sherry or madeira wine
  • 6 cups (1.4 L) low-sodium beef or chicken broth or vegetable stock
  • 2 cups (480 ml) Bacon Stock
  • 1 tablespoon beef or chicken base (optional; see Note)
  • 5 sprigs fresh thyme
  • 8 slices sourdough or French bread, ½ inch (12 mm) thick
  • 8 ounces (225 g) shredded Gruyère cheese
  • 4 ounces (115 g) thin-sliced bacon, diced and cooked until crisp
  • 2 tablespoons minced fresh chives


In a large Dutch oven or heavy pot over medium-low heat, melt the butter. Add the onions and spread them out in as thin a layer as possible and cook, stirring as needed to keep the onions from sticking, until they are very soft, a deep golden brown, and caramelized, about 1 hour.

Stir in the sherry and cook until completely reduced. Add the beef or chicken broth, bacon stock, base, and thyme and bring to a simmer. Cook, partially covered, for about 30 minutes, to allow the flavors to combine. Remove and discard the thyme sprigs.

Meanwhile, lightly toast the bread under the broiler; set aside. Ladle the hot soup into eight ovenproof bowls. Arrange the bowls on a baking pan and place 1 slice of toasted bread over each bowl of soup. Divide the cheese over the bread in each bowl and place under the broiler until the cheese is melted and crusty brown around the edges. Watch carefully so the cheese doesn’t burn. Garnish with the bacon and chives. Serve immediately.