Go Back

French Onion Soup

Classic French onion soup with slow-caramelized onions in a rich beef broth, topped with toasted bread and bubbly melted Gruyere. Cozy, elegant and easy.
Prep Time 15 minutes
Cook Time 1 hour 30 minutes
Total Time 1 hour 45 minutes
Course Soup
Cuisine American
Servings 6 servings
Calories 420 kcal

Ingredients
  

Soup:

  • 4 tbsp unsalted butter
  • 1 tbsp olive oil
  • 3 lb yellow onions about 5 large, halved and thinly sliced
  • 1 tsp salt plus more to taste
  • 1/2 tsp sugar optional, helps browning
  • 3 cloves garlic minced
  • 1/2 cup dry white wine or dry sherry or more broth
  • 8 cups low-sodium beef broth
  • 1 tbsp Worcestershire sauce
  • 1 tsp dried thyme or 4 fresh sprigs
  • 1 bay leaf
  • 1/2 tsp black pepper

Topping:

  • 6 slices baguette 1 inch thick
  • 8 oz Gruyere cheese shredded (about 2 cups)
  • 1/4 cup Parmesan cheese grated, optional

Instructions
 

  • Melt the butter with the olive oil in a large Dutch oven over medium heat. Add the onions and salt and stir to coat.
  • Cook, stirring every few minutes, for 45 to 60 minutes, until the onions are deep golden brown and jammy. Add the sugar after 15 minutes. Lower the heat if the bottom starts to burn and add a splash of water to loosen the brown bits.
  • Add the garlic and cook 1 minute. Pour in the wine and scrape the bottom of the pot. Simmer until almost gone, about 2 minutes.
  • Add the broth, Worcestershire, thyme, bay leaf and pepper. Simmer uncovered for 25 to 30 minutes. Remove the bay leaf and taste for salt.
  • Meanwhile, toast the baguette slices at 400°F (200°C) for 6 to 8 minutes until dry and crisp.
  • Set the oven to broil. Ladle the soup into oven-safe bowls on a baking sheet. Top each with a toast and a big handful of Gruyere (and Parmesan). Broil 2 to 4 minutes until bubbly and browned. Watch closely. Bowls will be very hot.

Notes

Make ahead: Make the soup (without the bread and cheese) up to 3 days ahead. The flavor gets deeper.
Storage: Refrigerate the soup up to 4 days or freeze up to 3 months. Store toasts separately in an airtight bag.
Reheat: Warm the soup on the stove until simmering, then add toast and cheese and broil.
Variations: Use a mix of beef and chicken broth, swap Gruyere for Swiss or provolone, or add a splash of brandy with the wine.
Keyword caramelized onion soup, easy french onion soup, french onion soup, homemade french onion soup