This French Onion Soup Recipe is made with slowly caramelized onions simmered in a rich beef and white wine broth, then topped with toasted baguette and plenty of bubbly Gruyère cheese. It takes a little patience to get those onions deeply golden and jammy, but that slow caramelization is what gives this classic soup its incredible depth of flavor.
Author’s Note
I recently went back into the kitchen to retest this recipe, and the biggest lesson was simple: don’t rush the onions.
Three pounds of thinly sliced onions took about 55 minutes in my cast-iron Dutch oven to become deeply golden, soft and jammy. I also eliminated the added sugar and flour from my original recipe, increased the garlic, and let the white wine reduce substantially before adding the beef broth.
The result is a simpler French onion soup with a deeper, more developed flavor and a method that relies on properly caramelizing the onions rather than trying to speed up the process.
French onion soup is made with relatively few ingredients, which means there really isn’t anywhere for shortcuts to hide. The onions are the foundation of the entire soup, and after retesting this recipe, I think giving them the time they need is far more important than trying to make this a quick soup.
-Silvia
Why you’ll love this recipe
- Deep, rich flavor: Slowly caramelizing the onions develops their natural sweetness and creates the foundation for the entire soup.
- No added sugar: Properly caramelized onions become naturally sweet, so I found there was simply no need for it.
- No flour: I prefer the rich but broth-forward consistency of French onion soup without flour.
- Simple ingredients: Onions, butter, olive oil, garlic, wine, beef broth and herbs do most of the work here.
- That classic cheesy topping: Toasted baguette and plenty of Gruyère are broiled until melted, bubbly and golden.
- Great for making ahead: Make the soup base ahead and add the bread and cheese just before serving.
Ingredients You’ll Need
- Yellow onions – you’ll need 3 pounds of yellow onions, thinly sliced. I prefer slicing rather than chopping the onions because those long, silky strands give French onion soup its characteristic texture.
- Butter and olive oil – I use 3 tablespoons butter and 1 tablespoon olive oil to caramelize the onions. The butter brings richness and flavor, while the olive oil helps coat that large amount of sliced onion as it begins to cook down.
- Garlic – I increased the garlic in this recipe to 4 cloves. Add it after the onions have caramelized so it doesn’t burn during their long cooking time.
- Dry white wine – you’ll need ½ cup dry white wine to deglaze the pot. Use the wine to loosen all of those flavorful browned bits from the bottom, then allow it to reduce substantially before adding the beef broth. I don’t rush this step. Reducing the wine concentrates its flavor and prevents the finished soup from tasting overly wine-forward. My suggestions are dry Sauvignon Blanc, Pinot Grigio or Chardonnay will work well.
- Beef broth – I use 4 cups of beef broth for that deep, savory flavor we associate with French onion soup. Since the broth plays such a large role in this recipe, use a good-quality one you enjoy. I prefer low-sodium broth when possible because it gives you more control over the seasoning as the soup reduces.
- Thyme and bay leaves – fresh thyme and 2 bay leaves add another layer of savory flavor to the broth without competing with the onions.
- Baguette – French baguette is my choice for that classic crusty bread topping. Toasting it first helps it hold up once it meets the hot broth.
- Gruyère cheese – gruyère is perfect for French onion soup because it melts beautifully and has a nutty, savory flavor that works so well with the sweet caramelized onions.
The Secret to Great French Onion Soup Is the Onions
If there’s one step you shouldn’t rush when making French onion soup, it’s caramelizing the onions.
I use 3 pounds of thinly sliced yellow onions for this recipe. At first, they will completely fill your pot. As they cook, they’ll release moisture, soften and dramatically reduce in volume before they really begin to caramelize.
In my cast-iron Dutch oven, this process took about 55 minutes.
Don’t stop when the onions are simply soft or lightly golden. For French onion soup, I want them deep golden brown, very soft and almost jammy.
You’ll also notice browned bits developing on the bottom of the pot as the onions caramelize. Scrape those bits back into the onions as you stir. That’s flavor!
As the onions get darker, you’ll need to stir more frequently to keep them from burning. If the bottom of the pot starts getting too dark before the onions are ready, add a small splash of water and scrape up the browned bits before continuing.
Most importantly, use the appearance of your onions rather than the clock to decide when they’re done. Yours may take 45 minutes, 55 minutes or even a little longer.
Does the Pot You Use Matter?
It can!
I tested this recipe in a cast-iron Dutch oven, which worked beautifully for slowly caramelizing such a large quantity of onions.
I recommend using a large, wide, heavy-bottomed Dutch oven or pot. You want enough room for the moisture released by 3 pounds of onions to evaporate as they cook.
If your pot is narrower, the onions may spend more time steaming before they begin browning. A lightweight pot may also develop hot spots more easily, so you’ll need to pay closer attention to your heat.
This is one reason caramelizing times can vary so much from kitchen to kitchen.
IMPORTANT TIP:
👉🏻 Don’t increase the heat to try to turn a 55-minute process into a 20-minute one. You risk browning or burning the outside of the onions before they’ve had enough time to soften, release their moisture and develop that deep caramelized flavor.
recipe at a glance
Method: Stovetop + broiler
Best pot: Large cast-iron Dutch oven or heavy-bottomed pot
Onions: 3 pounds yellow onions, thinly sliced
Caramelizing time: About 50–60 minutes
Wine: ½ cup dry white wine, reduced substantially
Broth: 4 cups beef broth
Simmer time: 25 minutes
Topping: Toasted baguette + Gruyère
Make ahead: Yes! the soup base can be prepared in advance
Freezer-friendly: Yes! (without the bread and cheese)
The biggest thing to know before you start: this isn’t a difficult soup, but it isn’t one to rush. Most of the cooking is hands-off or requires only occasional stirring, but properly caramelizing the onions is what builds the deep, savory-sweet flavor of the finished soup.
What To Serve with French Onion Soup
French onion soup is rich and satisfying enough to stand on its own, especially with the baguette and cheese topping, but I love pairing it with something fresh and seasonal like this apple cranberry frisée salad or this Brussels sprouts and apple salad.
Roasted carrots, honey roasted beets or roasted Brussels sprouts are also great options.
If you’re serving French onion soup as a starter, follow it with a simple roasted chicken, turkey breast, cider braised pork roast or another protein-forward main dish.
Looking For More Comforting Soups To Try?
French Onion Soup
Ingredients
- 3 lb onions thinly sliced
- 3 tbsp butter
- 2 tbsp olive oil divided
- salt to taste
- 4 cloves garlic minced
- 1/2 cup dry white wine
- 4 cups beef broth preferably low-sodium
- 1 sprig of fresh thyme
- 2 bay leaves
- 1 French baguette thinly sliced
- 1 cup shredded Gruyère cheese or enough to generously cover each bowl
Instructions
- Melt the butter with 1 tablespoon olive oil in a large cast-iron Dutch oven or other heavy-bottomed pot over medium heat. Add the sliced onions and season lightly with salt. Cook, stirring occasionally at first, until the onions begin to release their moisture and soften. As they reduce and begin browning, stir more frequently and scrape the bottom of the pot as needed.Continue cooking until the onions are deep golden brown, very soft and jammy, about 50–60 minutes.
- Add the minced garlic and cook for 30–60 seconds, stirring, just until fragrant.
- Pour in ½ cup dry white wine. Use a wooden spoon to scrape up the browned bits from the bottom of the pot. Let the wine simmer until it has reduced substantially and there is very little liquid pooling around the onions.
- Pour in 4 cups beef broth and add the fresh thyme and 2 bay leaves. Bring to a gentle simmer and cook uncovered for 25 minutes, allowing the flavors to develop.
- Remove the thyme stems and bay leaves. Taste and adjust with salt and freshly ground black pepper as needed.
Toasting the Baguette
- While the soup simmers, preheat the oven to 400°F.Arrange the baguette slices on a baking sheet and lightly brush them with remaining 1 tbsp olive oil. Bake for about 5 minutes, or until lightly golden and crisp.
Assemble the Soup
- Switch the oven to broil.Place oven-safe soup crocks on a rimmed baking sheet. Ladle the hot soup into the bowls and top each with a toasted baguette slice and a generous amount of shredded Gruyère.
- Broil for approximately 2–3 minutes, watching closely, until the cheese is melted, bubbly and golden brown in spots.Carefully remove from the oven and serve immediately. The bowls will be very hot.
Notes
Storage & Make Ahead
Refrigerator: Allow the soup to cool completely and store the soup base without the bread and cheese in an airtight container in the refrigerator for up to 3–4 days. Freezer: Freeze the cooled soup base in a freezer-safe container for up to 3 months. Do not freeze it with the baguette and Gruyère topping. Reheating: Thaw frozen soup overnight in the refrigerator if needed, then reheat gently on the stovetop until hot. Toast fresh baguette, assemble the bowls with Gruyère and broil just before serving. Make ahead: The soup base can be made several days ahead. In fact, this is a particularly convenient recipe to prep ahead because all you need to do before serving is reheat the soup, toast the bread and broil the cheese.Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
