French Onion Soup Recipe

Course: Appetizer, Soup

Cuisine: French

Prep Time: 20

Cook Time: 4 20

Total Time: 4 40

Servings: people

Calories: 674kcal

Author: Becky Hardin

This delicious French Onion Soup recipe serves up sweet onions in a rich broth, topped with melty cheese and crispy croutons. It's a classic soup with flavors that are out of this world!

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Equipment

Ingredients

For the Soup

2 tablespoons olive oil
4 tablespoons unsalted butter (½ stick)
1 clove garlic finely chopped
3 pounds yellow onions peeled, halved, and cut top to bottom into ⅛-inch slices
1 pound sweet yellow onions peeled, halved, and cut top to bottom into ⅛-inch slices
1¾ teaspoons kosher salt divided
8 cups low sodium chicken broth divided
¼ cup dry white wine
½ cup dry sherry
4 sprigs fresh thyme tied with kitchen twine
2 bay leaves
½ teaspoon freshly ground black pepper

For the Croutons

1 baguette cut into ½-inch cubes
2 tablespoons olive oil
2 tablespoons salted butter melted (¼ stick)
¼ teaspoon kosher salt
¼ teaspoon freshly ground black pepper

For the Topping

8 ounces shredded Gruyere or Swiss cheese (about 2 cups)
½ cup shredded Parmesan cheese
Chopped fresh parsley or thyme leaves optional

Instructions

For the Soup

Adjust oven rack to lower-middle position and preheat oven to 400°F. Spray a large Dutch oven with nonstick cooking spray.
Place the olive oil and butter in the pot and add the garlic and onions. Sprinkle with 1 teaspoon kosher salt and stir well. Cook, covered, for 1 hour until the onions have reduced in volume and have softened.
2 tablespoons olive oil, 4 tablespoons unsalted butter, 1 clove garlic, 3 pounds yellow onions, 1 pound sweet yellow onions, 1¾ teaspoons kosher salt
Remove the pot from the oven and stir, scraping the bottom and sides of the pan. Place the pot back into the oven and this time cover it with the lid left slightly ajar. Continue cooking the onions another 1 hour, and then give them another stir, scraping the bottom and sides of the pot. Return the pot to the oven, lid slightly ajar, and cook another 20-45 minutes or until the onions have completely softened and are golden brown.
Carefully remove the pot from the oven and place it on the stove over medium-high heat.
Cook the onions, stirring and scraping down the sides and bottom of the pot often, until the liquid evaporates and onions brown, 15-20 minutes. Reduce the heat to medium if the onions are browning too quickly. (Be careful NOT to burn the onions - the soup will be bitter.)
Continue cooking and stirring until the bottom of the pot has a dark coating, then stir in ¼ cup chicken broth, scraping the pot bottom and sides to deglaze the pot. Cook until the water evaporates and a dark crust coats the bottom of the pot, about 6-8 minutes. Add another ¼ cup of broth to deglaze the pot once again. Repeat the process twice more or until the onions are very dark in color.
8 cups low sodium chicken broth
Stir in the wine and the sherry and cook, stirring often, until the liquid has evaporated, about 3-5 minutes.
¼ cup dry white wine, ½ cup dry sherry
Add the remaining broth, thyme, bay leaves, freshly ground black pepper, ¾ teaspoon salt, and stir well. Scrape the sides and bottom of the pot to release any bits of browned bits of food. Increase heat to high and bring to a low boil.
4 sprigs fresh thyme, 2 bay leaves, ½ teaspoon freshly ground black pepper
Stir and reduce heat to low, cover, and simmer 30 minutes.
Remove the thyme stems and bay leaves and season with salt and pepper, if needed.

For the Croutons

Adjust oven rack to middle position and preheat oven to 350°F. Line a baking sheet with parchment paper.
In a medium bowl, toss together the cubed bread, olive oil, melted butter, ¼ teaspoon salt, and ¼ teaspoon black pepper. Turn the bread cubes onto the prepared baking sheet and use a rubber spatula to scrape any remaining oil and seasonings over the croutons, tossing to mix. Bake until golden in color and crispy, 15-18 minutes. Transfer the croutons to the original bowl; set aside.
1 baguette, 2 tablespoons olive oil, 2 tablespoons salted butter, ¼ teaspoon kosher salt, ¼ teaspoon freshly ground black pepper

To Serve

Increase oven temperature to 500°F (or set oven to "broil") and line the baking sheet with aluminum foil. Spray 6 oven-safe bowls/crocks with nonstick cooking spray and place them on the lined, rimmed baking sheet.
Divide the soup between the soup bowls (about 1½ cups each) and sprinkle with 2 tablespoons Gruyere. Top with croutons and sprinkle with the remaining Gruyere and then Parmesan. Broil for about 5-7 minutes, or until the cheeses are melted and gooey and the soup is bubbly around the edges. Let cool about 5 minutes before serving.
8 ounces shredded Gruyere or Swiss cheese, ½ cup shredded Parmesan cheese
Garnish with chopped parsley or fresh thyme leaves, if desired.
Chopped fresh parsley or thyme leaves

Video

Notes

To make this soup vegetarian, use vegetable broth instead of chicken broth.
You can also use beef broth in place of the chicken broth for a darker, richer flavor.
To make this soup gluten free, use gluten free croutons.
Instead of cutting it into croutons, slice the baguette into 1-inch slices and place a slice on top of each bowl of soup. Add cheese and broil.
If you're not a fan of wine or don't have any on hand, you can use an equal amount of broth in place of both the white wine and the sherry.
If you don't have broiler-safe bowls, I recommend slicing the baguette into 1-inch slices and broiling those with cheese on top on a baking sheet. Alternatively, you can toast the bread and cheese in the toaster oven if you don't have a broiler.
If you don't have a broiler AND you don't have a toaster oven, I recommend sprinkling a light layer of shredded cheese over top and letting the heat of the soup gently melt some of it.

Storage: Store French onion soup in an airtight container in the refrigerator for up to 3 days or in the freezer for up to 3 months.

Nutrition