Go Back
French Onion Chicken Soup Recipe
Ben Carraoli

French Onion Chicken Soup Recipe

I still remember the first time I made this French Onion Chicken Soup — it instantly became a comfort food classic in my kitchen. The smell of caramelized onions cooking low and slow filled the house and made me feel cozy before I even tasted a spoonful.
Print Recipe Pin Recipe
Total Time 1 hour 30 minutes
Servings: 6
Ingredients Method Notes

Ingredients
  

  • 4 cups sweet onion thinly sliced — Sweet onions caramelize beautifully and make the soup deeply flavorful.
  • 2 cups shallot thinly sliced — Adds delicate onion flavor that blends perfectly with the sweet onions.
  • 1 teaspoon kosher salt — Enhances all the savory flavors as the onions cook.
  • 1 2/3 tablespoons extra virgin olive oil — Helps the onions soften and caramelize slowly without burning.
  • 2 tablespoons all‑purpose flour — Lightly thickens the broth for a silky soup texture.
  • 1/4 cup light white wine — Adds acidity and depth that balances the sweet onions.
  • 1/4 cup sherry vinegar — Gives tang and richness in place of traditional sherry wine.
  • 4 fresh thyme sprigs — Fresh herbs infuse aromatic flavor as the soup simmers.
  • 2 dried bay leaves — Adds herbal undertones that deepen the broth.
  • 8 cups chicken bone broth — A rich protein‑packed base that makes this soup hearty.
  • 1 pound boneless skinless chicken thighs or breasts — Thighs are juicier; breasts are leaner.
  • 6 slices baguette or sourdough bread toasted — Classic topping that soaks up broth.
  • 12 thin slices Gruyere or Swiss cheese — Melts perfectly for golden gooey cheesy topping.

Method
 

  1. Start by heating olive oil in a large heavy pot over medium‑low heat. Add the sliced onions, shallots, and kosher salt. Cook slowly for about 30–40 minutes, stirring often, until the onions are soft, sweet, and golden brown.
  2. Sprinkle the flour over the caramelized onions and cook for a few minutes to remove the raw flour taste. Pour in the white wine and sherry vinegar, add thyme and bay leaves, and simmer uncovered for about 10 minutes to reduce the alcohol and build rich flavor.
  3. Pour in the chicken bone broth and add the chicken pieces. Bring the soup to a gentle boil, then reduce heat to low and simmer until the chicken is cooked through, about 25–30 minutes. Remove the chicken, shred it with two forks, and return it to the pot.
  4. Place toasted bread slices on top of each portion of soup in oven‑safe bowls. Layer with slices of Gruyere or Swiss cheese. Broil on low heat until the cheese bubbles and turns golden, about 2–3 minutes.
  5. Take the bowls out of the oven carefully. Let them cool slightly before serving so the cheesy topping sets a bit. Spoon the soup into bowls with the melted cheesy bread on top for a delicious, restaurant‑style presentation.

Notes

  • I caramelize the onions slowly and patiently — it brings out rich, sweet flavor.
  • I prefer bone broth for deeper savory notes and extra protein.
  • Toasting the bread before broiling helps it stay crisp under the cheese.
  • Using a mix of onions gives more complexity to the flavor.
  • I always taste for salt toward the end so it’s perfectly seasoned.