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Jessica T. Brown

Classic French Onion Soup

A hearty, savory French Onion Soup featuring slow-caramelized onions, rich beef broth, and a bubbly Gruyère topping. This classic dish is both comforting and nutritious, ideal for cozy dinners and effortless entertaining.
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Prep Time 20 minutes
Cook Time 1 hour 20 minutes
Total Time 1 hour 40 minutes
Servings: 4
Course: Soup
Cuisine: French
Ingredients Equipment Method Notes

Ingredients
  

  • 5 large yellow onions about 3½ pounds, peeled and thinly sliced
  • 2 garlic cloves finely minced
  • 4 tablespoons unsalted butter
  • 1 tablespoon olive oil
  • ½ teaspoon Worcestershire sauce
  • ¼ cup dry white wine
  • 5 cups beef broth preferably rich and flavorful
  • 2 sprigs fresh thyme plus extra for garnish
  • 1 bay leaf
  • ½ teaspoon kosher salt
  • ¼ teaspoon freshly ground black pepper
  • 4 thick slices of baguette or sourdough bread toasted lightly
  • 1¼ cups shredded Gruyère cheese about 3¾ ounces

Equipment

  • 1 Large Saucepan
  • 4 Broiler-Safe Soup Crocks
  • Kitchen Torch (optional)
  • 1 Rimmed Baking Sheet

Method
 

  1. Prepare the Aromatics: Start by peeling and slicing the onions as thinly as possible to ensure even cooking. Mince the garlic cloves finely to release their flavor during cooking.
  2. Begin Caramelizing Onions: In a large heavy-bottomed saucepan, melt the butter together with the olive oil over medium-low heat. Add the sliced onions and minced garlic along with a pinch of salt to help draw out moisture. Cook slowly, stirring occasionally, for about 30 minutes. The onions will start to soften and turn translucent.
  3. Deepen the Flavor: After 30 minutes, stir in the Worcestershire sauce. Continue cooking the onions gently, stirring more frequently now, scraping up any browned bits stuck to the bottom of the pan. This slow process should take about 30-40 more minutes until the onions become soft, richly browned, and fully caramelized. Be careful not to burn them—if the pan gets too dry, add a splash of water to loosen the browned bits.
  4. Deglaze and Build the Broth: Pour in the white wine and cook for a few minutes until the liquid has mostly evaporated, which will concentrate the flavors. Then add the beef broth, fresh thyme sprigs, and bay leaf. Season with salt and black pepper.
  5. Simmer the Soup: Bring the mixture to a gentle boil over medium-high heat. Reduce the heat slightly and let it simmer uncovered for 15 minutes to allow the flavors to meld beautifully.
  6. Final Seasoning and Remove Herbs: Discard the thyme sprigs and bay leaf. Taste the soup and adjust salt and pepper according to your preference.
  7. Assemble and Broil: Divide the hot soup evenly among four broiler-safe bowls. Place one slice of toasted bread on top of each portion. Sprinkle the shredded Gruyère generously over the bread and soup.
  8. Melt the Cheese: Place the bowls under a preheated broiler for about 3 to 4 minutes, or until the cheese is melted, bubbling, and lightly browned. If you don’t have a broiler-safe dish, use a kitchen torch to melt and brown the cheese carefully.
  9. Garnish and Serve: Finish by sprinkling fresh thyme leaves over each bowl and serve immediately for a warm, comforting meal

Notes

  • The key to a flavorful French Onion Soup lies in slowly caramelizing the onions over low heat to coax out their natural sweetness without burning. This step takes time but is worth every minute.
  • If your onions begin to stick or dry out during cooking, add a small amount of water to deglaze the pan and keep the onions moist.
  • For a thicker broth, whisk in 1 to 2 tablespoons of flour after the wine has reduced but before adding the beef broth.
  • Using broiler-safe soup crocks makes it easy to finish the dish in the oven and serve straight to the table. If unavailable, a kitchen torch or toaster oven can help melt and brown the cheese on separate toast slices.
  • Placing the soup bowls on a rimmed baking sheet helps transport them safely to the broiler and catches any bubbling spills.