French Onion Soup
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Caramelized onions, rich beef broth, and toasty bread topped with melted cheese, French onion soup is the ultimate comfort food.
Did you know that French onion soup, often a staple in restaurants, actually originated as a humble peasant soup made with just onions, stale bread, and water? Today’s versions might be a bit fancier, but this soup is still wonderfully simple to make at home. The key is patience. The onions need to be cooked low and slow so that they sweeten and turn a rich brown caramel color without burning. In addition to giving the onions the proper time and attention, I add a bit of sugar to enhance the sweetness of the onions, and I also stir in a bit of flour to add body to the broth—two tricks I picked up working in a French restaurant that made the best French onion soup ever. Finally, to add even more flavor, I top the croutons with two types of cheese.
If you don’t have ovenproof crocks for the soup, don’t worry—you can just top your soup with melty cheese toasts or serve them on the side. And if you want to get a head start, go ahead and make the broth and toasts several days ahead of time. When it’s time to eat, simply top the soup with the toasts and cheese and flash the crocks under the broiler. French onion soup pairs well with steak and/or a simple green salad.
Table of Contents
“I made this last night and it was 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
How To Make French Onion Soup
To begin, in a large Dutch oven or soup pot, melt the butter over medium heat. Add the oil, onions, salt, pepper, and sugar.
Cook, stirring occasionally, until the 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’ll need to stir them more frequently. Also, be sure to scrape the fond (or brown particles) from the bottom of the pan.
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.
Cook for about one minute to dissolve the flour.
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. Add the sherry, then 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 1/4 teaspoon sugar.
While the soup simmers, preheat the oven to 400°F and set an oven rack in the middle position. Arrange the baguette slices in a single layer on a baking sheet.
Bake until the bread is dry, crisp, and golden at edges, about 10 minutes. Set aside.
Adjust an oven rack 6 inches from broiler element and heat broiler. Set individual broiler-safe crocks on a baking sheet and divide the hot soup among the crocks. Be sure the soup is very hot as it won’t warm up much in the oven. Top each crock with 1 or 2 baguette slices (do not overlap slices).
Sprinkle evenly with Gruyère and then Parmigiano Reggiano.
Slide the crocks into the oven and broil until the cheese is melted and bubbly around edges, 3 to 5 minutes. (Alternatively, if using regular soup bowls: Top each toast slice with some cheese and return to broiler to melt, about 2 minutes more. Divide the soup among bowls and top each serving with two cheese toasts.)
Let the French onion soup crocks cool for a few minutes before serving.
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Video Tutorial
French Onion Soup
Caramelized onions, rich beef broth, and toasty bread topped with melted cheese, French onion soup is the ultimate comfort food.
Ingredients
- 4 tablespoons unsalted butter
- 1 tablespoon vegetable oil
- 3 pounds 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 slices
- 1 tablespoon dry sherry
- 8 ounces 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 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 inches from broiler element and heat broiler. Set individual broiler-safe crocks on a baking sheet and divide the hot soup among the crocks (be sure the soup is very hot as it won't warm up much in the oven). Top each crock with 1 or 2 baguette slices (do not overlap slices) and sprinkle evenly with Gruyère and then Parmigianno Reggiano. Slide the crocks into the oven and broil until the cheese is melted and bubbly around edges, 3 to 5 minutes. Let the crocks cool for a few minutes before serving. (Alternatively, if using regular soup bowls: Top each toast slice with some cheese and return to broiler to melt, about 2 minutes more. Divide the soup among bowls and top each serving with two cheese toasts.)
- Make-Ahead Instructions: The soup can be made and refrigerated up to 3 days ahead (without toasts or cheese), or up to 3 months ahead and frozen. Toasts can be made (without the cheese) and kept sealed at room temperature for up to 3 days.
Nutrition Information
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- Per serving (5 servings)
- Calories: 642
- Fat: 31 g
- Saturated fat: 17 g
- Carbohydrates: 53 g
- Sugar: 19 g
- Fiber: 4 g
- Protein: 31 g
- Sodium: 1,697 mg
- Cholesterol: 82 mg
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.