Chef Jenn’s Famous French Onion Soup

Who doesn’t love French Onion Soup? It’s oniony, cheesy, and packed with flavor. It’s also not a hard soup to make, but it’s so easy to go wrong. I’ve perfected this soup over my lifetime career as a chef, and let me tell you, this is the only French Onion Soup Recipe you’ll ever need.

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I love French Onion Soup, and I’m a huge foodie when it comes to soups. I’ve even written and published a soup cookbook, so I know my soups. French Onion Soup is one of those restaurant-quality soups that you can make at home, and it’s not hard to make! It takes some patience to caramelize the onions, but that’s the hardest part.

My French Onion Soup recipe is a little different than some others. First, it’s not thickened. I cringe when I see soup recipes that call for flour, cornstarch or other thickeners. This is a brothy soup, and the cheese will help thicken the liquid a bit.

This recipe also has both chicken and beef broth in it, plus a good glug of red wine. Soups that are made with just beef broth are too beefy, and chicken broth isn’t rich enough. But the combination of both broths plus the wine is magic.

Ingredients

• Butter – I cook with salted butter, but unsalted works just as well if you prefer to control the seasoning.
• Onions – Yellow onions are my first choice for their sweetness, but white onions are a great substitute.
• Bay leaves – One or two are plenty; remove them before serving.
• Fresh thyme sprigs – Fresh thyme gives the best flavor, but ½ teaspoon dried thyme per sprig will work in a pinch.
• Red wine – Use a dry red wine you’d enjoy drinking, or substitute additional beef broth if you prefer to cook without wine.
• Beef broth – I use low- or no-sodium broth so I can control the seasoning.
• Chicken broth – Low- or no-sodium broth works best and adds depth without overpowering the onions.
• Gruyère cheese – Buy a block and grate it yourself for the smoothest melt.
• Baguette slices – Day-old baguette toasts up especially well and stays crisp longer under the cheese.

How to Make French Onion Soup

Scroll down for the full recipe card with exact measurements and printable instructions.

Melt the butter in a large soup pot or Dutch oven over medium heat.

Reduce the heat to medium-low and add the onions, bay leaf, and thyme sprigs. Cook for 30 to 40 minutes, stirring frequently, until the onions are soft and deeply golden brown. Be patient during this step because slow caramelization develops the rich, sweet flavor that gives French onion soup its signature taste. A wooden spoon is helpful for stirring and scraping up any browned bits as the onions cook.

Pour in the red wine and scrape the bottom of the pot to loosen any caramelized bits. Let the wine simmer until it has reduced to just a thin layer in the bottom of the pot.

Add the beef broth and chicken broth, stirring to combine. Bring the soup to a gentle boil.

Reduce the heat and let the soup simmer for about 20 minutes so the flavors can blend together. Before serving, remove the bay leaf and thyme sprigs.

While the soup simmers, preheat your oven’s broiler.

Ladle the hot soup into oven-safe bowls, leaving enough room for the bread and cheese. Place a couple of toasted baguette slices on top of each bowl. Toasting the bread first helps it hold its shape once it’s added to the soup.

Sprinkle a generous layer of grated Gruyère cheese over the baguette slices, making sure they are well covered.

Broil for a few minutes, watching closely, until the cheese is melted, bubbly, and golden brown.

Carefully remove the bowls from the oven and let them cool for a minute or two before serving. Enjoy!

Chef Jenn’s Tips

• Slow and steady wins the race; take your time caramelizing the onions to unlock their natural sweetness.
• If you don’t have fresh thyme, use ¼ teaspoon of dried thyme.
• You can use Spanish or Vidalia onions, but your soup will be sweeter.
• Season the soup well, but remember that cheese is salty and will add more salt to your soup. I under season the soup by just a wee bit to account for salty cheese.

Best Cheese For French Onion Soup

Gruyere cheese is my top choice for this soup because it melts wonderfully and has a rich, complex, nutty flavor. But, it can be expensive. Some other good alternatives are Parmesan, Swiss, or even mozzarella. Just don’t skimp on the cheese!

Make It A Meal

French Onion Soup stands splendidly on its own, but it can also be part of a more substantial meal. Pair it with a crisp, green salad dressed in a light vinaigrette to add a fresh contrast to the rich soup. For a heartier option, consider serving it alongside a grilled steak or a homey dish like German Pot Roast.

Storage

French Onion Soup stores beautifully, making it a great make-ahead dish. Allow the soup to cool completely before transferring it to an airtight container. It will be kept in the refrigerator for up to 4 days without the bread and cheese topping. Store those separately. If you’d like to freeze it, omit the cheese and bread topping, and freeze the soup for up to 3 months. Thaw it overnight in the fridge and reheat gently on the stove, adding fresh cheese and toasted baguette slices before serving.