How to Make the Perfect Classic French Onion Soup
French · Medium · 110 min · 4 servings
A deeply caramelized onion soup topped with crusty bread and a golden layer of melted Gruyere cheese. This timeless French bistro classic is pure comfort in a bowl.
Why this recipe works
This Classic French Onion Soup recipe has been crafted to deliver restaurant-quality results in your home kitchen. At just 110 minutes from start to finish, it fits perfectly into a busy schedule without sacrificing flavor. Each serving comes in at 430 calories with 18g of protein, making it a balanced choice for any meal.
What you will need
This recipe uses 10 simple ingredients that you can find at any grocery store:
- 4 large yellow onions thinly sliced
- 4 tbsp unsalted butter
- 1 tbsp olive oil
- 0.5 cup dry white wine
- 4 cups beef broth
- 1 tbsp fresh thyme leaves
- 4 thick slices baguette toasted
- 1.5 cups Gruyere cheese shredded
- 1 tsp sugar
- 2 cloves garlic minced
Step by step instructions
Step 1: Caramelize the Onions
Melt butter with olive oil in a heavy pot over medium low heat. Add all the sliced onions and sugar, then cook slowly for 60 to 70 minutes stirring every 10 minutes until deeply golden brown and caramelized. Do not rush this step.
Step 2: Deglaze and Build Broth
Add garlic and cook for 1 minute. Pour in the white wine and scrape up all the browned bits from the bottom of the pot. Cook for 3 minutes until the wine reduces by half.
Step 3: Simmer the Soup
Add the beef broth and thyme to the pot. Bring to a boil, then reduce heat and simmer uncovered for 20 minutes. Taste and season generously with salt and black pepper.
Step 4: Assemble the Crocks
Preheat your broiler to high. Ladle the hot soup into oven safe crocks or bowls placed on a baking sheet. Place a toasted baguette slice on top of each bowl and pile the shredded Gruyere generously over the bread.
Step 5: Broil and Serve
Place the baking sheet under the broiler for 3 to 4 minutes until the cheese is fully melted, bubbling, and golden brown in spots. Watch carefully to avoid burning. Serve immediately with caution as the bowls will be very hot.
Easy substitutions
Missing an ingredient? Here are some swaps that work perfectly:
- Gruyere cheese → Swiss or Emmental cheese for a similar melting quality
- dry white wine → dry vermouth or additional beef broth
- beef broth → vegetable broth to make the soup vegetarian
Common mistakes to avoid
Watch out for these pitfalls that can affect your results:
- Rushing the caramelization process by using high heat which burns the onions instead of sweetening them
- Using sweet onions instead of yellow onions which do not develop the same savory depth
- Not using oven safe bowls which can crack or shatter under the broiler
Nutrition facts
Per serving: 430 calories, 18g protein, 38g carbs, 22g fat, 4g fiber.
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