Caramelizing the Onions
- Heat the Oil and Butter:
- In a large pot or Dutch oven, heat the olive oil and butter over medium heat until melted.
- Add the Onions:
- Add the thinly sliced onions to the pot and stir to coat them in the oil and butter.
- Caramelize the Onions:
- Cook the onions, stirring frequently, for about 30-40 minutes, until they are soft, golden brown, and caramelized.
- After about 15 minutes, add 1 teaspoon of sugar to help the onions caramelize and become sweet. Be patient with this step as it’s essential to the soup’s flavor.
- Add Garlic:
- Stir in the minced garlic and cook for another 1-2 minutes until fragrant.
Building the Soup
- Add the Flour:
- Sprinkle the flour over the caramelized onions and stir to combine. Cook for about 2 minutes to get rid of the raw flour taste. This will help thicken the soup slightly.
- Deglaze with Wine (Optional):
- Add the white wine to the pot, scraping up any browned bits from the bottom. Let the wine simmer for 2-3 minutes until mostly evaporated.
- Add Broth and Herbs:
- Pour in the beef broth, add the bay leaf and thyme, and bring the soup to a simmer. Reduce the heat to low, cover, and let it simmer for 30-40 minutes to develop the flavors.
- Season:
- Remove the thyme sprigs and bay leaf. Taste the soup and season with salt and pepper as needed.
Preparing the Topping
- Toast the Baguette:
- While the soup simmers, preheat your oven to 400°F (200°C). Place the baguette slices on a baking sheet and toast them in the oven for about 5-7 minutes, until golden and crisp.
- Add Cheese:
- Remove the baguette slices from the oven and top them with a generous amount of grated Gruyère cheese (and Parmesan if using).
Assembling the Soup
- Broil the Topping:
- Set your oven to broil. Ladle the soup into oven-safe bowls, place a toasted baguette slice on top of each, and sprinkle with additional Gruyère cheese.
- Melt the Cheese:
- Place the bowls on a baking sheet and broil in the oven for 2-3 minutes, until the cheese is melted, bubbly, and golden brown.
Serving
- Garnish and Serve:
- Serve the French Onion Soup hot, garnished with fresh thyme or a sprinkle of Parmesan if desired. Be careful when serving as the bowls will be hot from the broiler.
- Enjoy: Break through the cheesy, crispy top to enjoy the savory, sweet, and richly flavored soup beneath.
Tips for Success
- Onions: Be patient when caramelizing the onions. They need to cook slowly to release their natural sugars, which gives the soup its signature sweetness.
- Broth: Homemade beef broth or a high-quality low-sodium beef broth works best for deep flavor.
- Cheese: Gruyère is the traditional choice for this dish, but Swiss or even a sharp white cheddar can work as a substitute.
Conclusion
French Onion Soup is the ultimate comfort dish that combines caramelized onions, rich broth, crispy baguette, and melted cheese. Whether you’re serving it as an appetizer or a main course, this dish is sure to impress with its depth of flavor and cozy warmth.
This recipe provides all the steps to create a French Onion Soup that’s every bit as delicious as the ones served in French bistros. Enjoy this cozy classic with your loved ones!