Ingredients:

  • 2 tablespoons (30ml) unsalted butter, plus extra for toasting bread if desired
  • 2 tablespoons (30ml) olive oil
  • 3 large yellow onions (about 2 pounds/900g total), thinly sliced
  • 2 cloves garlic, minced
  • 1 teaspoon (5ml) granulated sugar
  • 1/2 teaspoon (2.5ml) dried thyme
  • 1/4 teaspoon (1.25ml) dried bay leaf
  • 6 cups (1.4 liters) beef broth (low sodium preferred)
  • 1 cup (240ml) dry red wine (optional, but recommended - something like a Cabernet Sauvignon or Merlot works well)
  • Salt and freshly ground black pepper to taste
  • 4 thick slices of baguette (about 1 inch/2.5cm thick)
  • 8 ounces (225g) Gruyère cheese, grated
  • 4 ounces (113g) Swiss cheese, grated
  • Optional: Fresh parsley, chopped, for garnish

Instructions:

  1. Melt butter and olive oil in the Dutch oven over medium heat. Add onions, garlic, sugar, thyme, and bay leaf. Cook, stirring occasionally, until the onions are deeply caramelized and golden brown (about 45-60 minutes). This takes time, so be patient! A little bit of fond (the brown stuff stuck to the bottom of the pot) is your friend, but don't let it burn. Deglaze the pan with a splash of broth if necessary.
  2. Pour in the red wine (if using) and bring to a simmer, scraping up any browned bits from the bottom of the pot. Add the beef broth. Season with salt and pepper to taste. Bring to a simmer, then reduce heat and let simmer for at least 15 minutes to allow the flavors to meld. Remove the bay leaf.
  3. Preheat your oven to 400°F (200°C). Lightly brush the baguette slices with melted butter (optional). Toast in the oven for 5-7 minutes, or until lightly golden. Alternatively, toast under the broiler, watching carefully to prevent burning.
  4. Preheat your broiler. Ladle the soup into oven-safe bowls or ramekins. Place a toasted baguette slice on top of each bowl. Combine the Gruyère and Swiss cheeses in a bowl, then generously pile the cheese mixture on top of the bread in each bowl.
  5. Place the bowls on a baking sheet and broil until the cheese is melted, bubbly, and golden brown (about 2-3 minutes). Watch carefully, as broilers can vary in intensity.
  6. Garnish with fresh parsley (optional) and serve immediately while the cheese is still molten and gloriously stretchy.