Traditional French Onion Soup (Soupe à l'oignon gratinée)
Traditional French Onion Soup (Soupe à l'oignon gratinée)
Ingredients
- •3 lb yellow onions, peeled and thinly sliced
- •3 tablespoon unsalted butter
- •1 tablespoon olive oil
- •1 teaspoon granulated sugar
- •1 teaspoon salt
- •0.5 teaspoon freshly ground black pepper
- •1 tablespoon all-purpose flour
- •0.5 cup dry white wine (such as Sauvignon Blanc or dry sherry)
- •6 cup beef broth, high quality, low sodium
- •1 leaf bay leaf
- •3 sprigs fresh thyme sprigs
- •8 slices day-old baguette, sliced 1-inch thick
- •6 oz Gruyère cheese, grated
Instructions
- 1.
In a large, heavy-bottomed pot or Dutch oven, melt the unsalted butter and olive oil over medium-low heat. Add the thinly sliced onions, granulated sugar (if using), 1 teaspoon of salt, and 0.5 teaspoon of freshly ground black pepper.
- 2.
Cook the onions slowly, stirring frequently, for 45-60 minutes, or until they are deeply caramelized to a rich, golden-brown color. This process requires patience; do not rush it. If the onions start to stick to the bottom, add a tablespoon of water or broth to deglaze the pot and scrape up any browned bits.
- 3.
Sprinkle the all-purpose flour over the caramelized onions and stir continuously for 1-2 minutes to cook out the raw flour taste.
- 4.
Pour in the dry white wine or dry sherry. Scrape the bottom of the pot with a wooden spoon to deglaze thoroughly, loosening any remaining browned bits. Cook for 2-3 minutes until the wine has mostly evaporated.
- 5.
Add the beef broth, bay leaf, and fresh thyme sprigs to the pot. Bring the soup to a gentle simmer, then reduce the heat to low, cover partially, and let it cook for at least 20-30 minutes to allow the flavors to meld. Taste and adjust seasoning with additional salt and pepper as needed. Remove the bay leaf and thyme sprigs before serving.
- 6.
While the soup simmers, preheat your oven broiler. Arrange the baguette slices on a baking sheet and toast lightly under the broiler until golden on both sides. Watch them closely to prevent burning.
- 7.
Ladle the hot French onion soup into individual oven-safe bowls. Place 2 toasted baguette slices on top of the soup in each bowl.
- 8.
Generously sprinkle the grated Gruyère cheese over the baguette slices, ensuring the cheese covers the bread and slightly overlaps the rim of the bowl.
- 9.
Place the bowls on a baking sheet (for easier handling and to catch any drips) and broil for 2-5 minutes, watching very carefully, until the cheese is melted, bubbly, and deeply golden brown. It can go from perfect to burnt quickly.
- 10.
Serve immediately, being extremely careful as the bowls and their contents will be very hot.
Tips
- 💡Patience is Key: The slow caramelization of the onions is the absolute heart of this soup. Do not rush this step; low and slow heat is crucial for developing the deep, rich flavor without burning the onions.
- 💡Quality Broth Matters: A high-quality beef broth or homemade beef stock will make a significant difference in the final taste of your soup. Avoid thin, watery broths.
- 💡Choose the Right Cheese: Gruyère is the traditional choice for its nutty flavor and excellent melting properties, creating that perfect golden crust. Comté or Emmental are good substitutes if Gruyère is unavailable.
- 💡Oven-Safe Bowls: Always ensure your serving bowls are oven and broiler-safe to prevent cracking. Placing them on a baking sheet also makes them easier and safer to transfer in and out of the hot oven.
- 💡Watch the Broiler Closely: Broilers are powerful and can quickly burn the cheese. Keep a constant eye on the soup during the gratinéing step to achieve a beautiful, bubbly, golden-brown crust without overcooking.
Recipe from TheCookbook.ai
Created by Basil Roux