French Onion Soup is a comforting and flavorful classic that’s perfect for chilly days. The rich, caramelized onions meld beautifully with the savory beef broth, topped with crusty bread and melted cheese for a truly satisfying experience. This soup is both hearty and elegant, making it a great choice for a cozy dinner or a special occasion. With a little patience, you’ll create a dish that is both simple and deeply flavorful.
Caramelize the Onions. In a large pot, melt the butter with the olive oil over medium heat. Add the sliced onions and cook, stirring frequently, until they begin to soften. This will take about 10 minutes.
Add Sugar and Garlic. Sprinkle the sugar over the onions to help them caramelize and add the minced garlic. Continue cooking the onions, stirring occasionally, until they are deeply browned and caramelized. This should take an additional 30-40 minutes. Be patient, as this step is key to the soup’s deep flavor.
Deglaze the Pot. If using, add the white wine to the pot to deglaze, scraping up any browned bits from the bottom of the pot. Let the wine simmer until it has reduced by half.
Add Broth and Herbs. Pour in the beef broth, add the bay leaf and thyme, and bring the soup to a simmer. Let it cook for another 20 minutes, allowing the flavors to meld together.
Season and Prepare to Serve. Remove the bay leaf, taste the soup, and season with salt and pepper as needed.
Prepare the Topping. Ladle the soup into oven-safe bowls. Place a slice of toasted baguette on top of each bowl, then generously sprinkle the grated Gruyère cheese over the bread.
Broil and Serve. Place the bowls under the broiler for a few minutes, just until the cheese is melted and bubbly. Serve immediately, being careful as the bowls will be hot.
The key to a great French Onion Soup is slowly caramelizing the onions. Don’t rush this step; the longer you cook them, the more flavorful the soup will be. For a richer flavor, you can use a combination of beef and chicken broth. Gruyère is traditional, but you can also use Swiss or a mix of cheeses for a different flavor profile. The white wine adds a nice depth to the soup, but you can omit it if you prefer.