Our delicious French Onion Soup recipe is made with caramelized onions in a rich beef broth. It's simple, authentic, and the perfect warm and cozy dish for winter.
Looking for more French cuisine? Try a Croque Madame, Potato Leek Soup, or a Monte Cristo Sandwich!
Why I love this soup:
Comforting – This classic French Onion Soup recipe is made with caramelized onions and beef stock then topped with toasted bread and cheese. It has a delicious sweet onion taste and it's irresistible on a chilly day!
Authentic – This recipe comes from our family friend who is a phenomenal cook, and lived in France. It's every bit as delicious as French Onion Soup I've enjoyed on my visits to Paris. Serve it as a main course with a simple green salad, or a side dish to Croque Monsieur, Croque Madame, or 40 cloves garlic chicken.
How to make French Onion Soup:
Caramelize Onions: Add butter and onions to a large pot and cook until they are softened. Pour in sugar and stir until the onions become golden brown and caramelized, about 25 minutes.
Add flour and cook for a couple more minutes. Add beef stock, wine, thyme, celery, and bay leaves then cook for 30 minutes.
Toast Bread: Brush the bread with melted butter and broil until toasted.
Sprinkle with Cheese: To assemble, place bread on top of a bowl of soup, sprinkle with cheese and broil until cheese is melted!
Recipe Variations:
- Croutons: Croutons are often used on top of French onion soup. If you don't want to bother broiling a baguette, they work great too.
- Vegetarian: Substitute vegetable broth for the beef broth along with 1 tablespoons of soy sauce. This will add a richness that will help mimic the richness of the beef broth.
- Vegan: Make the same substitution listed for Vegetarian, substitute olive oil for the butter, and use hemp seed crumble cheese and vegan gruyere.
- Gluten Free: Substitute gluten-free flour and gluten free artisan bread.
Make Ahead and Freezing Instructions:
- Make Ahead Instructions: The soup base can be made a day in advance, stored in the fridge. Wait to add the bread and cheese until ready to serve. Reheat the soup on the stove, and then ladle into oven-safe bowls, add the bread and cheese. and broil.
- Freezing Instructions: Store the soup, without bread and cheese, in a freezer safe container and freeze for up to 3 months. (The shredded cheese and bread may also be frozen separately).
More Classic Soup Recipes:
- Matzo Ball Soup
- Lentil Soup
- Roasted Cauliflower Soup
- Chicken Tortilla Soup
- Chicken and Dumplings
- Beef Noodle Soup
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Recipe
French Onion Soup
Ingredients
- 1 1/2 pounds onions (about 3 large onions), thinly sliced
- 3 Tablespoons butter
- 1/4 teaspoon granulated sugar
- 1/4 teaspoon salt
- 2 Tablespoons all-purpose flour
- 6 cups low-sodium beef broth
- 1/2 cup white wine
- 1/2 teaspoon dried thyme
- 1 piece celery , just a small chunk, not the whole rib
- 2 bay leaves
- 8 slices French Baguette
- 4 Tablespoons butter , melted
- 2 cloves garlic , halved
- 1 cup Gruyere cheese* , fresh grated
- 1/3 cup freshly grated parmesan cheese
Instructions
- Caramelize onions: Add butter and onions to a large pot over medium heat. Season with a little salt and pepper and cook until softened. Add sugar and continue to gently stir until onions become golden brown and caramelized, about 25 minutes. Careful to not let them burn! Maintain a medium to medium-low heat.
- Add the flour and cook for 3 more minutes. Add beef stock, wine, thyme, celery, and bay leaves. Cook partially covered for 30 minutes.
- Preheat oven to 350 degrees F.
- Toast bread: Arrange bread on a baking sheet and brush with melted butter on both sides. Bake for 15 minutes, flipping to the other side half way through. Remove from oven and rub a cut clove of garlic onto each piece of bread.
- Broil: Turn oven to High broil. Remove bay leaves and the piece of celery from the soup and ladle soup into 4 oven proof bowls. Place the toasted bread on top of each bowl. Depending on the size of your bowls you may need two slices of bread. Sprinkle the tops generously with both types of cheese. Broil until the cheese is browned and bubbling.
Notes
- Cheese: Could substitute Swiss.
- Make Ahead Instructions: The soup base can be made a day in advance, stored in the fridge. Wait to add the bread and cheese until ready to serve. Reheat the soup on the stove, and then ladle into oven-safe bowls, add the bread and cheese. and broil,
- Freezing Instructions: Store the soup, without bread and cheese, in a freezer safe container and freeze for up to 3 months. (The shredded cheese and bread may also be frozen separately).
Nutrition
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I originally shared this recipe November 2016. Updated February 2020 and February 2024.
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French Onion Soup is my husbands favourite so his opinion was going to be what counts most. I used sweet sherry instead of white wine. The result was delicious. Husband gave it a big thumbs up. I loved it too. Thanks.
I used a mandolin to slice my onions thin and it took a while to caramelize them. By the end they were pretty much mush… is that normal? Should I slice thicker?
Sorry Casey! I’m not sure how thin you sliced them, but it sounds like maybe yes, you could slice them a little thicker. They will definitely be soft and “caramelized” but they shouldn’t be messy.
This is very close to my very favorite recipe in which I use a Swiss Gruyere and a semi-sweet white wine, the soup this way is always a smash hit. The type of bread is critical, needed is bread that will not absorb the soup then turn to mush and sink to the bottom = a total failure. Swiss Gruyere is similar to the traditional Raclette cheese used in Switzerland. If once you’ve had traditional Raclette as they do it in Switzerland, you won’t forget it ever, it’s so good, with a semi-sweet nutty flavor. That flavor in a Swiss Gruyere cheese combined with a semi-sweet white wine is always a winning combination. When I lived in Canada, friends always asked me to make it for them in winter. I rate this recipe at 4 stars because you don’t have an option for 4 1/2 stars. My favorite recipe is the only soup of this type that I’d rate at 5 stars.
Then why not share your recipe that way we could try both and see for ourselves which is better?
hello! i’m so excited to try this recipe. i see that it serves four but how much is a serving?
Hi Amie, I didn’t write down exactly how much it makes, but I would estimate about 8 cups. Hope you get a chance to try it!
What is the serving size and how many servings per recipe? Thanks.
Hi Danielle,
This recipe makes about 8 cups of soup- about 4 hearty servings!
Hello, what is the best white wine to cook with, for this recipe? Thank you ?
Hi Lynn,
I would use pinot grigio or Chardonnay!
What type of onion are you using; white or yellow?
What type of onion are you using; white or yellow?
I’ve been making this for years. It is outstanding. The only differences are grated Romano and mozzarella instead of Gruyere. This also makes it Italian onion soup.
I just made this recipe and it was Delicious! Thank you for sharing ~ <3
I’m so glad you liked it! Thanks for commenting 🙂
Do you know of a substitution for white wine?
I would substitute chicken or veggie broth.
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