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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I’m looking forward to trying your recipe with one change-I haven’t found a store beef broth I like and hardly ever make one, so I use chicken broth and a can of condensed beef consommé. It helps with making it mellow tasting. Your onion cooking tips make such good sense. Can’t wait 😊 and will come back to rate.
A yummy recipe…..except that I caramelize the onions overnight on the low setting in my crockpot. No stirring or over-browning. Onions are ready for the soup or for any recipe which calls for caramelized onions.
We don’t do alcohol. Do you have any suggestions on substitutions? Thanks
Hi J, It’s fine to leave it out. You might just add a tablespoon of lemon juice for a touch of acidity. Hope you enjoy it!
Thank you soooooo much for creating and sharing this recipe! We’ve stalked your blog weekly hoping we’d see a French Onion Soup recipe. We are making it this weekend 😃
Hope you enjoy!!
Do you have nutritional values available?
I just added them – hope you enjoy! 🙂
I’m making this next week. I love onion soup and this recipe looks great. I will have to depart from one of your instructions: “Once I get the onions going, I like to pour myself a glass of wine, call a girlfriend, and putter around the kitchen.”
The wine and puttering are O.K. but my wife will strenuously object to me calling a girlfriend. 🙂
😂
I am so happy that you posted this recipe today. My family loves French onion soup, and I can’t wait to make this tonight! Thank you for always coming up with new inspirations.
Question: I have had NO luck finding a commercial beef broth with any real flavor, so, unless I have a homemade beef broth (which is rare), I have been using chicken broth when making French onion soup. I will definitely be trying out your recipe; do you have any suggestions regarding substituting chicken broth?
Hi Kate, you can substitute chicken broth with no additional adjustments. (I’ve seen plenty of onion soup recipes that utilize chicken broth instead of beef broth.) Hope you enjoy! 🙂
Hi,
So happy I found you! Just received your new cookbook and I cannot wait to begin cooking!
As to the beef broth in your recipe (see Kate 2/7/19 comment): there is a fantastic new product available from More Than Gourmet called “Kitchen Accomplice” concentrate which comes in the absolute most wonderful beef flavor (+ chicken, vegetable, even bone broth!). It is a professional chef grade product and the concentrate makes the equivalent of like 27 boxes of broth. There is such authentic beef flavor you will be amazed. It elevates anything you use it in — I squirt a teaspoon in anything I’m making that is beef, like Stroganoff or Stew. I gave some Kitchen Accomplice as a gift to a gourmet cook friend of mine, and she can’t stop thanking me for discovering it and sharing this secret weapon with her! I have nothing to do with the company, I’m just a customer of the web site and a huge fan because it is such an outstanding product (and the convenience is that once opened, it lasts six months in the frig!). I do hope you’ll give it a try; it made this soup so rich and deeply flavorful, and I used it in place of adding more Worcestershire. I also use many stock and sauce products from More Than Gourmet, and if you’re not familiar with them I think you would be interested in this line; you can read all about them online). Hope it is OK that I shared this. Feel free to edit my review or not publish at all; I really just wanted to pass this along to YOU! Thanks again!
This is great info, Nancy – thank you!
A national name brand soup company has beef consommé in cans in your local grocery, that is what the FO soup recipe I use calls for. I think it is better than the box stuff. I also find that the little packets in the instant oodle noodle packages make for a flavorful base stock in a pinch. I know they aren’t the best health wise, but they do have flavor when you are out of bouillon or don’t have chicken or beef stock in the cupboard. I do watch adding any additional salt to whatever recipe if I use those. I live in the country so you do what ya gotta do when there is no store to run to. 🙂
I LOVE to make stock for FO soup w/the leftover liquid/broth from the classic slow roasted chuck roast w/onion soup mix, potatoes, onions, celery, mushrooms, and carrots. I add extra water to the crock pot so I will have more liquid to use as stock to make the FO soup. I strain out any tidbits of meat and veg, and chill overnight so I can skim off any fat. The flavor from the simmered vegetables w/the beef makes it sooo good! It makes all the difference in richness and flavor. It also freezes well, because I agree, homemade French Onion soup is a lazy day puttering project! Salad croutons also make for a great substitute when you don’t have a baguette on hand. That living in the country thing again!
Jenn your the best! Thank you!😉
Awww… thanks Kerrie! ❤
This almost exactly matches the recipe I use all the time, and it’s excellent. The only difference is that I use homemade chicken stock, instead of beef broth. The result is very close to the beef broth, but the chicken stock is more available to me, and it allows the onions to shine.