French Onion Soup
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With deeply caramelized onions, a rich, savory broth, toasted bread, and plenty of bubbling cheese, this French onion soup recipe is perfect for a chilly day.
I learned how to make this French onion soup recipe while working at a French restaurant known for the dish, and the most important lesson was not to rush the onions. Cooking them slowly until deeply golden and almost jammy gives the soup its signature sweetness and depth of flavor.
A few other touches make a difference: a little flour gives the broth some body, sherry adds depth, and a combination of Gruyère and Parmigiano-Reggiano makes for an especially flavorful topping. It takes some time, but most of it is hands-off—and the result is every bit as satisfying as the French onion soup you’d order at a good restaurant.
“Amazing! I think it was even better than the French onion soup we had in Paris last summer.”
What You’ll Need To Make French Onion Soup
- Sweet onions: The star of the soup. Sweet onions caramelize beautifully, becoming deeply golden and almost jammy as they cook. Yellow onions will also work well.
- Butter & olive oil: Used together to slowly caramelize the onions, adding richness while helping them cook evenly.
- Flour: Just a small amount gives the broth a little body without making it thick or gravy-like.
- White wine & dry sherry: Add acidity and depth and help loosen the flavorful browned bits from the bottom of the pot. There’s no need to splurge on an expensive wine, but use a dry white you’d enjoy drinking. For the sherry, choose a dry drinking sherry rather than cooking sherry.
- Beef broth & Worcestershire sauce: Create the savory backbone of the soup. Worcestershire adds an extra layer of umami without calling attention to itself.
- Thyme & bay leaves: Add subtle herbal flavor as the soup simmers.
- Baguette: Toasted slices soak up some of the broth while providing a sturdy base for all that melted cheese.
- Gruyère & Parmigiano-Reggiano: Gruyère melts beautifully and has the nutty flavor traditionally associated with French onion soup; Parmigiano-Reggiano adds a salty, savory finish.
- Jump to the printable recipe for precise measurements
How To Make French Onion Soup
Caramelize the onions: This is the step you don’t want to rush. Cook the onions slowly until deeply golden, soft, and almost jammy. Stir occasionally at first, then more often as they darken, scraping up the flavorful browned bits from the bottom of the pot. If they brown too quickly, add a splash of water to loosen the fond and keep it from burning.
Deglaze and simmer the soup: Pour in the wine and scrape up all that flavorful fond, then let it cook down until the onions are jammy again. Stir in the flour, followed by the broth, Worcestershire, and herbs, and let the soup simmer until the flavors come together. The sherry goes in at the end to deepen the broth.
Toast the baguette: While the soup simmers, toast the baguette slices until they’re dry, crisp, and golden around the edges. You want them nice and sturdy so they can soak up some broth without completely falling apart.
Assemble and broil: Ladle the hot soup into oven-safe crocks, top with the toasted baguette, and pile on the Gruyère and Parmigiano-Reggiano. Broil until the cheese is melted, bubbling, and browned around the edges. Give the crocks a few minutes to cool before digging in—they’ll be very hot.
Video Tutorial
More Cozy Soup Recipes You’ll Love
Classic French Onion Soup
Ingredients
- 4 tablespoons unsalted butter
- 1 tablespoon vegetable oil
- 3 lbs Vidalia (or sweet onions) (about 5 medium), halved lengthwise and thinly sliced
- ¾ teaspoon salt
- ½ teaspoon freshly ground black pepper
- ¾ teaspoon granulated sugar
- 1 cup dry white wine
- 2 tablespoons all-purpose flour
- 6 cups beef broth
- 1 teaspoon Worcestershire sauce
- ½ teaspoon dried thyme
- 2 bay leaves
- 1 small baguette, cut into ½-in (13-mm) slices
- 1 tablespoon dry sherry
- 8 oz Gruyère cheese grated (about 2 heaping cups; look for one imported from Switzerland)
- ½ cup grated Parmigiano Reggiano
Instructions
- In a large Dutch oven or soup pot, melt the butter over medium heat. Add the oil, onions, salt, pepper, and sugar. Cook, uncovered, stirring occasionally with a wooden spoon, until onions are deep golden brown and caramelized, 45 to 55 minutes. In the beginning, you will only need to stir the onions occasionally. As they start to brown midway through cooking, you will need to stir them frequently, scraping the fond (the brown particles) from the bottom of the pan. If the onions are browning too quickly, reduce the heat slightly or add a few tablespoons of water to deglaze the pan and continue cooking.
- Add the wine and raise the heat to high. Cook, stirring with a wooden spoon to scrape any fond from the bottom of the pan, until almost all of the liquid has evaporated and the onions are jammy, 8 to 10 minutes.
- Add the flour and cook, stirring constantly, for one minute.
- Add the broth, Worcestershire sauce, thyme, and bay leaves to the pot. Bring to a boil, reduce the heat to a simmer, and cook, covered, for about 30 minutes.
- While the soup simmers, preheat the oven to 400°F (205°C) and set an oven rack in the middle position. Arrange the baguette slices in a single layer on a baking sheet and bake until the bread is dry, crisp, and golden at edges, about 10 minutes. Set aside.
- When the soup is finished, remove the bay leaves and add the sherry; taste and adjust seasoning if necessary. If the soup needs a deeper flavor, try a few shakes of Worcestershire sauce. If it’s not quite sweet enough, add ¼ teaspoon sugar.
- Adjust an oven rack 6 in (15 cm) from the broiler element and heat the broiler. Place the oven-proof crocks on a baking sheet (see note below if you don’t have oven-proof crocks). Fill them with very hot soup, top each with 1 or 2 baguette slices without overlapping, and sprinkle evenly with Gruyère and Parmigiano Reggiano. Broil until the cheese is melted and bubbly around the edges, 3 to 5 minutes. Let the crocks cool for a few minutes before serving.
Notes
- If you don’t have oven-proof soup crocks, place the toast slices on a baking sheet, top each with cheese, and broil for about 2 minutes, until the cheese is melted. Divide the hot soup among regular bowls and top each serving with the cheese toasts.
- Make-Ahead Instructions: The soup can be made and refrigerated up to 3 days ahead (without toasts or cheese), or frozen for up to 3 months. The toasts can be made (without the cheese) and kept sealed at room temperature for up to 3 days.
Nutrition Information
This website is written and produced for informational purposes only. I am not a certified nutritionist and the nutritional data on this site has not been evaluated or approved by a nutritionist or the Food and Drug Administration. Nutritional information is offered as a courtesy and should not be construed as a guarantee. The data is calculated through an online nutritional calculator, Edamam.com. Although I do my best to provide accurate nutritional information, these figures should be considered estimates only. Varying factors such as product types or brands purchased, natural fluctuations in fresh produce, and the way ingredients are processed change the effective nutritional information in any given recipe. Furthermore, different online calculators provide different results depending on their own nutrition fact sources and algorithms. To obtain the most accurate nutritional information in a given recipe, you should calculate the nutritional information with the actual ingredients used in your recipe, using your preferred nutrition calculator.
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Excellent recipe, easy to make and delicious. I don’t add the sherry cos I don’t have it.
Disappointing. I followed the recipe exactly except no sherry on hand. I had high expectations for this but very little flavor at all. I finally added a packet of Lipton onion soup mix for flavor.
This recipe is great! It turned out so tasty!!
This was the first time I made onion soup. I liked the flavor a lot, but my onions broke down into very small pieces. When I have had onion soup in restaurants, the spoonful’s have pieces (almost strings) of onions. Did I do something wrong?
It sounds like it could have been one of three things – maybe you sliced the onions too thinly, cooked the soup a bit too long, or stirred the onions a little much. Hope that helps for next time around!
A little too sweet for me. I used homemade beef broth and was expecting a deeply rich soup but it was mainly sweet. I’ll omit the sugar next time but I can’t imagine the small amount included the recipe caused it to be overly sweet. I will try it again!
Rather one note in my opinion. Easy recipe. Just not enough depth of flavor for my taste. Made it a second time with red wine instead of white and it was more to my liking. Over all, a good basic recipe. Will def use going forward with some small changes like the wine and adding some garlic. Thank you!
I have a much loved but more complicated recipe for French Onion Soup which gives it super depth of flavor. It calls for deep red wine, like a merlot, and some port. About 1/2 cup of each once you get the onions carmelized. I used this recipe on once upon a chef because I didn’t have any wine at the time, and didn’t want to run to the store. This recipe is good, but I think you would be much happier with the addition of the wines. Just make sure to add enough cooking time for the alcohol taste to cook off. Make sure you cut the onions bigger to accommodate the longer cooking time so you won’t have mush. Enjoy!
Absolutely delicious! Followed the recipe exactly with the exception of the sherry ( none on hand) and it was perfectly flavorful and silky smooth. Can’t wait to make it again, Thank you!
I agree with those that said not enough depth of flavor. I added more Worcester a bit more salt and some salt free bullion beef, that perked up the flavor a bit but for such a lengthy recipe I would have hoped it would be more flavorful
This is a very good recipe. Just made it. It’s fantastic.
Easy to follow recipe with delicious results
Made this last night and it was really good, despite a few substitutions because I was too lazy to go to the store. I would make this again. I think the secret is making sure the broth used is of good quality. Awesome recipe!