Ingredients:
- 3 lbs (1.36 kg) yellow onions, thinly sliced
- 4 tbsp (60 ml) unsalted butter
- 2 tbsp (30 ml) olive oil
- 1 tsp granulated sugar
- 1/2 tsp dried thyme
- 1/4 cup (60 ml) dry Sherry or dry white wine (optional)
- 8 cups (1.9 liters) beef broth or stock
- 2 bay leaves
- Salt and freshly ground black pepper to taste
- 6 thick slices of baguette, about 1-inch thick
- 2 tbsp (30 ml) olive oil
- 8 oz (225 g) Gruyère cheese, grated
Instructions:
- Melt butter and olive oil in the Dutch oven. Add onions, sugar, thyme, salt and pepper. Cook over medium-low heat, stirring occasionally, until deeply caramelized and golden brown (about 60-70 minutes).
- If using, deglaze the pot with sherry or white wine, scraping up any browned bits from the bottom. Add beef broth and bay leaves. Bring to a simmer.
- Reduce heat and simmer for at least 30 minutes to allow flavors to meld. Taste and adjust seasoning as needed.
- Brush baguette slices with olive oil and bake or broil until golden brown and crispy.
- Preheat broiler. Ladle soup into oven-safe bowls. Top each bowl with a crouton or two, and then generously cover with Gruyère cheese. Broil until cheese is melted, bubbly, and golden brown.
- Serve hot, and be careful – those bowls will be scorching!