French Onion Soup

This French onion soup is made like the classic, with plenty of onions and leeks in a rich homemade broth. Here’s how to make it.

Most French onion soup recipes create a gooey, stringy, clingy cheese trampoline that clamps down on the soup dish as it melts, creating a sight to behold but a mess to eat in polite company. Not this recipe, which calls for a simple sprinkling of cheese on toasted bread rather than over the entire bowl. This not only makes for easier eating but a little more room to experience the complexity of the blend of caramelized red and yellow onions as well as leeks. It also means you can indulge your whim for French onion soup even when you don’t have a cheese with Super Glue-like stick-to-it-iveness.–Renee Schettler


If you look at a classic recipe for French onion soup, it’s always beef broth. This recipe lightens it up a little bit by swapping it out for chicken broth, to great effect. You could even go vegetarian with a vegetable broth, but the most important thing is the quality of the broth used. French onion soup is mostly just broth and onions, so you want to be certain that you’re using the good stuff.

French Onion Soup

A ceramic soup bowl filled with French onion soup, and topped with melted cheese which is dripping down the side of the bowl.
This French onion soup is made like the classic, with plenty of onions and leeks in a rich homemade broth. Here’s how to make it.
Frank Mentesana and Jerome Audureau

Prep 25 mins
Cook 1 hr 35 mins
Total 2 hrs
6 servings
327 kcal
5 from 1 vote
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  • 2 large yellow onions quartered and thinly sliced
  • 2 red onions quartered and thinly sliced
  • 4 leeks root ends and dark-green tops lopped off, leeks sliced 1/4-inch thin, and washed
  • 1 tablespoon (1/2 oz) unsalted butter
  • 1 tablespoon olive oil
  • 2 tablespoons unbleached all-purpose flour
  • 8 cups vegetable or chicken stock
  • 1 tablespoon Worcestershire sauce [Editor’s Note: or a splash of fortified wine]
  • 1 teaspoon salt
  • 1/2 teaspoon freshly ground black pepper
  • 1 day-old baguette
  • 1/2 cup grated Parmigiano-Reggiano cheese
  • 1/2 cup grated Gruyère cheese (or substitute Comté, Emmentaler, mozzarella, young Manchego, or another melting cheese) plus more as needed


  • In a large soup pot over medium-high heat, sauté the yellow and red onions and the leeks in the butter and olive oil stirring occasionally to keep the onions from sticking to the bottom of the pot and scorching, until they’ve begun to soften slightly and shrink in volume, 5 to 10 minutes.
  • Reduce the heat to medium or medium-low and continue to cook the onions for about an hour, until they’re caramel in color and seem practically melted. Keep a careful eye on them, as you don’t want the onions to burn. If it looks like they’re heading in that direction, lower the flame even more, or splash a little bit of water over them to buy you some cooking time.
  • Sprinkle the properly caramelized onions with the flour, stirring constantly so the flour doesn’t clump. Sauté for another 5 minutes to cook off the floury taste.
  • Pour the stock over the onions and bring to a boil over high heat. Reduce the heat and simmer for 30 minutes. Stir in the Worcestershire sauce, salt, and pepper. Taste and adjust the seasonings accordingly.
  • Preheat your oven to 350°F (175°C). Thickly slice the baguette, brush both sides with olive oil, scatter them on a baking sheet, and bake until the bread dries out and the edges are golden brown. Preheat the broiler.
  • Just before you're ready to serve the soup, whisk in the Parmigiano-Reggiano. It's important to whisk in the cheese at the last minute or it will sink to the bottom of the pot and burn. Ladle the warm soup into heatproof bowls or crocks and float a slice of the baked bread in each bowl. Sprinkle some Gruyère over each slice of bread and slide the crocks under the broiler until the cheese bubbles and browns. 
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Show Nutrition

Serving: 1portionCalories: 327kcal (16%)Carbohydrates: 44g (15%)Protein: 12g (24%)Fat: 12g (18%)Saturated Fat: 5g (31%)Polyunsaturated Fat: 1gMonounsaturated Fat: 4gTrans Fat: 1gCholesterol: 23mg (8%)Sodium: 2110mg (92%)Potassium: 324mg (9%)Fiber: 4g (17%)Sugar: 9g (10%)Vitamin A: 1889IU (38%)Vitamin C: 14mg (17%)Calcium: 302mg (30%)Iron: 3mg (17%)

Recipe Testers’ Reviews

Revelation: The BEST French onion soup ever is NOT made with beef stock. Using chicken stock was a real revelation. We really enjoyed this soup.

The addition of red onion and leeks really made for a richer soup. And the onions were cut in smaller pieces than specified in other recipes, so they didn’t dribble down our chins when we were spooning them out of the bowl. We used a combination of regular Gruyère and an aged Gruyère for the topping and it was superb. Our house guest, who had said he wasn’t a fan of French onion soup, ate his all up and asked for seconds.

Rich and sweet, the soup balances well with the saltiness of the Gruyère crouton on top. Although it’s just as good without the crouton.

It takes some time to pull all the ingredients together, but it’s still a simple recipe and definitely worth the effort. It will make a great snow day meal, sometime.

Originally published January 13, 2003


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  1. 5 stars
    I made 1/2 recipe yesterday and was immediately enlightened. My chef always told me to only use yellow onions for French onion soup, so I broke the rules. The soup had a sweetness previously untasted and caused probably by the leeks. Thank you for this taste bomb.

  2. How do you make the top gooey and burnt? We tried it last night but it did not form a cheese top over the crock.

    1. Barbara, my guess, as Beth indicates, is the broiler. How long did you keep it under the flame? It needs time to melt and brown. Also you want to keep it not too close (where it will burn) and not too far (where it will take a long time to brown).

    2. Hi Barbara,

      Sorry that you did not get a gooey-licious cheese top. Perhaps a bit more cheese? How long did you run it under the broiler? Let us know if you try it again.

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