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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Hi. I am hesitant to use my broiler because my baking sheet came with instructions that said not to use it at any temp above 450 degrees. Could I use a kitchen torch instead?
Sure, Shannon, I think that should work. Enjoy!
What is a “broiler”?
Hi Jon, a broiler is a heating element in your oven that provides very high heat. Cooking food close to the broiler is similar to grilling, but with the heat directly above versus below your food. The great majority of ovens should have a broiler setting. Hope that clarifies!
I saved about 3-4 cups of broth from a pot roast. It had all the herbs and spice needed. After refrigeration, I strained out the chunks of veggies, meat and fat. The pot roast already had some red wine in it from deglazing the sauté pan but, you can’t go wrong adding sherry. Scaled up to about 20 servings, it needed a couple more pints of beef broth in addition. The pot roast broth was already reduced and loaded with potato starch so it didn’t need much time reducing the broth. No sugar, no flour, no Worcestershire sauce. It went over really well.
Made this for first time. It was delicious! Did not add any sugar or the sherry.
Definitely a keeper.
Delicious. Easy!! I only had port, not sherry, but it was still delicious!!
I had the same first impression that many others here did, that the soup was way too sweet; so to mitigate the sweetness I added an extra tablespoon of sherry, 2 tablespoons more of white wine and about another half teaspoon of black pepper. Initially I wasn’t going to use sherry because I detest it, but it actually mixed well with the flavor of the broth. I went ahead and assembled a bowl of the soup with the bread and cheese for the broiler, and I must say it was quite tasty (though I’m not convinced the overall recipe was worth the time it took to make). The only thing I will do differently on the next bowl is omit the sharp Italian cheese and just use gruyere and/or one of the milder cheeses some others suggest.
I love French Onion Soup and your recipe is pretty close to the classic version. I love it!
I did change a couple of things, mainly because I didn’t have them on hand. First, instead of white sugar, I added a very small amount (about a 1/2 teaspoon) of molasses for sweetness and depth of flavor. Too much would have really changed the flavor, but just this small amount helped with the browning of the onions and gave it some complexity.
Second, I didn’t have any beef stock, so I used vegetable stock instead. No biggie.
Third, I didn’t have an worchestershire sauce either, so I added a splash of Thai fish sauce and a splash of Liquid Aminos, along with a dash of black pepper to make up for it. That worked fine.
Fourth, I didn’t have any sherry, which I usually keep in the pantry, so I had to omit it. I did add a splash of wine near the end instead and that made it quite nice.
My end result was not the classic onion soup, but it was close and delicious, none the less.
I made this soup and it came out beautifully. It was delicious and it made such a lovely presentation. I am going to make it again this week. Everyone loved it.
I thought the recipe was very good. I added an extra tbsp of flour, a clove of minced garlic and another pinch of sugar. Perhaps the people who didn’t like it did not caramelize the onions completely or let the soup cook down enough once complete. Before the final simmer I felt like the soup needed something and was a little bland but after I let it cook down it turned out great.
We made this last night and I agree with some other comments that the soup lacked flavor. I added Worchester sauce and balsamic vinegar like other comments suggested and that helped some. We love your recipes, but were not fond of this soup.
I made this two days ago and here is my take: it is an excellent recipe and letting it sit in the frig overnight really enhances the flavors.
However, for me, the next time I make it will will omit the bay leaves and add beef bullion to get a beefier taste with the onions.
I will make this again no doubt, but with a couple of personal adjustments.
Thank you for this delicious recipe!