French Onion Soup

A cozy, classic French onion soup made with deeply caramelized onions and rich beef bone broth.

5 from 1 rating

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Author: April Anderson

Servings: servings

Prep Time: 20

Cook Time: 1 30

Total Time: 1 50

Ingredients

¼ cup unsalted butter
2 pounds yellow onions sliced ¼” thick
½ teaspoon kosher salt
½ cup dry white wine see note
2 tablespoons all-purpose flour
48 ounces beef bone broth
8 sprigs fresh thyme see note
1 bay leaf
4 ounces French bread sliced (see note)
8 ounces Gruyere cheese shredded
chopped parsley for garnish

Instructions

Melt ¼ cup of butter in a 10” pot over medium-high heat. Add the sliced onions and ½ teaspoon of salt. Stir to coat the onions in the butter. Stir them often for 10 minutes and then adjust the heat to medium to medium-low.
Cook the onions, stirring occasionally, until they have released their moisture and are golden and soft. In a 10” pot, this will take between an hour and an hour and a half. While they cook, stir them occasionally. If they are browning too quickly, lower the heat.
In the last 20 to 30 minutes of cooking time, once they have started to turn more golden, adjust the heat to medium. Stir them often so they caramelize evenly. They are ready when they are deeply golden in color and soft.
Once the onions are caramelized, add ½ cup of wine. Stir and cook the onions in the wine for about a minute or so, scraping up all the browned bits off the pan. Sprinkle 2 tablespoons of flour over the top and stir it into the onions.
Add the bone broth and stir. There should be no lumps of flour. Add the bay leaf and thyme sprigs. Simmer the soup for 15 to 20 minutes, stirring occasionally.
While the soup simmers, toast the bread slices and set them aside.
Turn the oven broiler to high. Take the bay leaf and thyme sprigs out of the soup and discard them. Place 4 (12-ounce) oven-safe soup bowls on a sheet pan. This will make it easier to transfer them to and from the oven.
Ladle the soup into the bowls. Place the toasted bread on top. Sprinkle the cheese on top, keeping most of it on top of the bread (some will end up in the soup, which is just fine).
Place the sheet pan under the broiler. Broil the cheese until it’s melted – this will only take a couple of minutes. Serve the soup and enjoy!

Notes

If you use a pot that is larger or smaller than 10”, the cooking time for the onions will vary. The onions will cook faster in a larger pot and will take more time in a smaller one.

A Sauvignon Blanc or Pinot Grigio are both great options for this soup.

Use a small bunch of thyme that has eight or so sprigs to make it easy to fish the whole thing out once the soup is simmered.

I like to use a long, thin baguette so the slices are smaller and fit easily in the bowls. If you use larger bread, cut the pieces to fit the bowls you are using. I like to add two pieces of bread in each bowl of soup, but you can add as much as you want (or serve extra on the side). The one on the bottom will soak up some of the soup while the one on top stays toasty and crisp.

You can make the soup a day or two in advance and keep it in the refrigerator. When you’re ready to serve it, warm it up on the stove, assemble the soup bowls with the bread and cheese, and broil before serving.

Nutrition Estimate

Course: Soup

Cuisine: French

Keyword: classic french onion soup, French onion soup with bone broth