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French Onion Soup

This classic French Onion Soup is built through the slow caramelization of sliced onions, which develop a deep, sweet flavor and rich aroma. The onions are simmered in a savory broth until tender, then topped with toasted bread and melted cheese for a comforting, golden final appearance. The process emphasizes patience and layering flavors for a soulful, deeply satisfying bowl.
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Prep Time 15 minutes
Cook Time 50 minutes
Total Time 1 hour 5 minutes
Servings: 4
Course: Main Course
Cuisine: French
Calories: 320
Ingredients Equipment Method Notes

Ingredients
  

  • 4-5 large yellow onions preferably large, sweet onions
  • 2 tablespoons unsalted butter
  • 0.5 cup dry white wine optional, for deglazing
  • 4 cups beef broth or vegetable/mushroom broth for vegetarian option
  • 2 sprigs fresh thyme or 1 teaspoon dried thyme
  • to taste salt and black pepper
  • 1 baguette sliced baguette preferably day-old for better crisping
  • 1 ½ cups Gruyère cheese finely grated

Equipment

  • Large heavy-bottomed pot or Dutch oven
  • Sharp knife
  • Wooden spoon
  • Ovenproof bowls or crocks
  • Baking sheet

Method
 

  1. Peel and thinly slice the onions uniformly, aiming for about 0.3-inch slices. This helps them cook evenly and caramelize beautifully.
  2. Warm your large heavy-bottomed pot over medium-low heat and add the butter. Wait until it melts and begins to foam gently, releasing a toasty aroma.
  3. Add the sliced onions to the pot, stirring well to coat them with butter. Cook gently, stirring every 5-7 minutes, until they soften and start to turn translucent, about 15 minutes. The onions will begin to release a sweet aroma.
  4. Continue cooking the onions over low heat, stirring frequently. After about 20-25 minutes, they will deepen in color to a rich golden amber and smell sweet and caramelized.
  5. Pour in the white wine, scraping the bottom of the pot with your spoon to loosen any browned bits. Let the wine simmer for 2-3 minutes until slightly reduced, adding brightness to the sweetness of the onions.
  6. Add the beef broth along with the sprigs of thyme. Bring the mixture to a gentle simmer and cook uncovered for 20-30 minutes, stirring occasionally to develop a rich, layered flavor. Season with salt and pepper to taste.
  7. Meanwhile, slice the baguette into ½-inch rounds and toast them on a baking sheet until golden and crispy, about 8 minutes. Optionally, rub the slices with a garlic clove for extra aroma.
  8. Remove the thyme sprigs from the soup and taste; adjust seasoning if needed. Ladle the hot soup into ovenproof bowls, placing a toasted baguette slice on top of each.
  9. Sprinkle the grated Gruyère generously over the bread and place the bowls on a baking sheet. Broil in the oven until the cheese bubbles and turns golden, about 3-5 minutes—watch carefully to avoid burning.
  10. Carefully remove the bowls from the oven and let sit for a minute. Serve hot, with the cheese melted and bubbly, and enjoy the rich, caramelized flavors in every spoonful.

Notes

Patience is key in caramelizing onions; it takes time but results in a deeply flavorful, sweet base. Feel free to experiment with different cheeses or broth types for personalized variations.