French Onion Soup with Gruyère (Printable)

Rich, comforting soup featuring slowly caramelized onions in beef broth, finished with toasted bread and melted Gruyère.

# What You Need:

→ Onions

01 - 6 large yellow onions, thinly sliced
02 - 2 tablespoons unsalted butter
03 - 1 tablespoon olive oil

→ Broth

04 - 6 cups beef broth, or vegetable broth for vegetarian option
05 - 1/2 cup dry white wine, optional

→ Flavorings

06 - 2 cloves garlic, minced
07 - 1 teaspoon sugar
08 - 1 teaspoon salt
09 - 1/2 teaspoon freshly ground black pepper
10 - 2 sprigs fresh thyme, or 1/2 teaspoon dried thyme
11 - 1 bay leaf

→ Topping

12 - 4 slices crusty French bread, about 1 inch thick
13 - 2 cups grated Gruyère cheese

# Directions:

01 - In a large heavy-bottomed pot, melt the butter with the olive oil over medium heat. Add the sliced onions and cook, stirring occasionally, until softened, approximately 15 minutes.
02 - Sprinkle the onions with sugar and salt. Continue to cook, stirring frequently, until the onions are deeply golden and caramelized, approximately 30 to 40 minutes.
03 - Add the minced garlic and cook for 1 minute more.
04 - Pour in the white wine if using and scrape up any browned bits from the bottom of the pot. Simmer for 2 to 3 minutes.
05 - Add the beef broth, thyme, bay leaf, and black pepper. Bring to a boil, then reduce heat and simmer uncovered for 30 minutes. Remove and discard the thyme sprigs and bay leaf.
06 - Preheat the broiler. Arrange the bread slices on a baking sheet and toast under the broiler until lightly golden on both sides.
07 - Ladle the hot soup into oven-safe bowls. Top each with a slice of toasted bread and a generous handful of Gruyère cheese.
08 - Place the bowls under the broiler until the cheese is melted and bubbling, 2 to 3 minutes. Serve immediately.

# Expert Advice:

01 -
  • The caramelization process is meditative, and watching those pale onions turn deep amber feels like actual magic happening on your stove.
  • It's a complete meal in a bowl that feels fancy enough for guests but honest enough to make on a Tuesday night just for yourself.
  • One pot, minimal cleanup, maximum comfort—the kind of soup that justifies turning on the oven.
02 -
  • The caramelization cannot be rushed—I learned this the hard way by turning up the heat midway through and ending up with burnt rather than caramelized onions that tasted acrid instead of sweet.
  • Don't skip removing the thyme sprigs and bay leaf before serving, as biting into them unexpectedly is the opposite of pleasant and will pull someone right out of the moment.
  • The broiler time at the end is crucial but easy to botch—too long and the cheese becomes tough and separates, so stay in the kitchen and watch it happen rather than wandering away thinking you have time.
03 -
  • Use a heavy-bottomed pot because thin pots create hot spots that scorch the bottom onions while the sides barely brown—the weight of cast iron or a quality Dutch oven makes a real difference in even caramelization.
  • Keep a damp kitchen towel nearby while broiling so you can safely pull the hot bowls out—oven mitts work but the towel gives you more control, and you'll thank yourself when you're not fumbling with something this hot.
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