Ingredients:
- 3 pounds (about 6 large) yellow onions
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 1/2 teaspoon sugar
- 2 large garlic cloves, minced
- 1/2 cup dry sherry
- 8 cups beef stock
- 1 teaspoon salt
- 1 bay leaf
- Fresh thyme sprigs
- 1 baguette
- Olive oil for brushing the baguette
- 8 ounces Gruyère cheese, shredded
Instructions:
- Prepare the onions by peeling and thinly slicing them.
- In a large pot, melt the butter with olive oil.
- Add the onions and cook over medium heat for 10 minutes until tender.
- Sprinkle with sugar to aid caramelization, then cook for an additional 30-45 minutes until golden.
- Add minced garlic and sauté for one minute.
- Pour in the dry sherry, scrape the pot bottom, and cook until it evaporates.
- Pour in the beef stock, season with salt, add the bay leaf and thyme. Bring to a boil, then simmer for 30 minutes.
- Prepare croutons by slicing the baguette, brushing with olive oil, and baking until golden.
- Sprinkle Gruyère cheese on the croutons and melt under the broiler.
- Remove the bay leaf and thyme from the soup. Adjust salt.
- Serve the soup in bowls, top with melted cheese croutons, and enjoy!
Tips:
- Use yellow onions for better caramelization.
- Avoid increasing the heat during caramelization to prevent burning.
- Prepare croutons just before serving to maintain their crispy texture.
- The soup can be made ahead and reheated before serving.
- Add more Gruyère cheese if desired, as it adds a delicious flavor.