French Onion Chicken Soup Recipe with Gruyere

This high-protein French Onion Chicken Soup combines slowly caramelized onions, savory bone broth, tender shredded chicken and a golden layer of melted cheese to deliver a comforting, satisfying meal that’s perfect for cooler evenings or any time you want a cozy dinner.

French Onion Chicken Soup

This version takes the classic French onion soup flavors—deeply caramelized onions, a splash of wine, and melted cheese over toasted bread—and boosts the protein by adding chicken and bone broth. It yields about six servings and provides a hearty, balanced main-dish soup with about 40 grams of protein per serving. If you enjoy the same flavor profile without broth, consider making a skillet-style French onion chicken instead.

Ingredients and Tips

This recipe follows the structure of traditional French onion soup but adds chicken and bone broth for extra nutrition and substance. The ingredient list below gives the specific amounts used; read the tips to help you get the best texture and flavor.

• Onions: A mix of sweet onions and shallots works wonderfully. Slice them thin and allow plenty of time to caramelize for a naturally sweet, savory base.
• Salt and oil: Cook the onions slowly in olive oil and season lightly to draw out moisture and accelerate caramelization.
• Flour: A small amount helps slightly thicken and round out the broth; use gluten-free flour if needed.
• Light white wine: Adds acidity and complexity. Any dry white will do; reduce it to cook off the alcohol.
• Sherry vinegar: Adds depth and a subtle tang when wine is not used or to complement it.
• Herbs: Fresh thyme and bay leaves lend classic aromatic notes as the soup simmers.
• Bone broth: Boosts savory umami and protein; plain chicken stock also works if bone broth isn’t available.
• Chicken: Boneless, skinless thighs stay moist and shred easily; breasts can be used as a leaner option.
• Bread and cheese: Traditional toasted baguette or sourdough topped with Gruyere or Swiss creates the iconic crusty, melty topping. For a low-carb option, skip the bread and broil cheese directly on the soup.

How to Make French Onion Chicken Soup

Caramelizing onions takes time, but most of the process is hands-off. While the onions slowly brown, you can prepare other ingredients or do light kitchen tasks. The full printable instructions and exact measurements are in the recipe card below.

1. Caramelize the onions: In a large heavy pot or Dutch oven, heat olive oil over medium–low. Add thinly sliced sweet onions and shallots with a pinch of salt. Cook, stirring often, until soft and deeply golden—about 30–40 minutes. Cover the pot between stirs if the onions are drying out to retain moisture and encourage even browning.
2. Add flour and wine: Sprinkle the flour over the onions and cook for 2–3 minutes to remove the raw taste. Stir in the white wine, sherry vinegar, thyme and bay leaves. Simmer uncovered for about 10 minutes to reduce and concentrate flavors.
3. Simmer with chicken: Add bone broth and the chicken pieces. Bring to a boil, then lower the heat to a gentle simmer. Cook until the chicken is cooked through, about 25–30 minutes.
4. Shred and season: Remove the chicken, shred with forks, then return it to the pot. Taste and adjust seasoning, removing bay leaves and thyme stems before serving.
5. Finish with bread and cheese: Ladle the soup into oven-safe bowls (about 1½ cups per bowl). Top each bowl with a toasted round of baguette and a slice of Gruyere or Swiss. Place the bowls on a baking sheet and broil on low until the cheese melts and bubbles, about 2–3 minutes. For a low-carb option, skip the bread and broil cheese directly on the soup.

Variations

• Use any combination of onions (Vidalia, yellow, white or red) to change sweetness and depth.
• Omit wine and replace it with a little extra broth if you prefer an alcohol-free version.
• Swap sherry vinegar with red wine vinegar for a different acidic note.
• Replace thyme with rosemary for a bolder herb profile.
• Try shredded beef instead of chicken for a richer, more robust stew-like soup.
• Choose fontina, mozzarella or provolone in place of Gruyere for a milder melt.
• Keep it dairy-free by omitting the cheese or using a dairy-free melting alternative.
• Make cheesy croutons on a baking sheet if you don’t have oven-safe bowls: toast the bread, top with cheese and finish in the oven, then place croutons on the soup.

Serving Suggestions

• Simple green salad: A crisp salad with a tangy vinaigrette cuts through the soup’s richness—arugula or mixed greens work well.
• Roasted vegetables: Roasted Brussels sprouts, asparagus or broccoli add color, texture and extra vegetables to the meal.

Storage

• Refrigerate: Store soup (without bread and cheese) for up to 4 days in an airtight container.
• Freeze: Freeze portions without cheese or bread for up to 3 months. Thaw in the refrigerator before reheating.
• Reheat: Warm on the stove or in the microwave, then add toasted bread and cheese and broil to re-create the melted topping if desired.

Ingredients

• 4 cups sweet onion, thinly sliced (from 4 medium/large)
• 2 cups shallots, thinly sliced (about 4)
• 1 teaspoon kosher salt
• 1 2/3 tablespoons extra virgin olive oil
• 2 tablespoons all-purpose flour (or gluten-free flour)
• 1/4 cup light white wine
• 1/4 cup sherry vinegar
• 4 fresh thyme sprigs
• 2 dried bay leaves
• 8 cups chicken bone broth (or chicken stock)
• 1 pound boneless skinless chicken thighs or breasts
• 6 slices baguette or sourdough, toasted
• 12 thin slices Gruyere or Swiss cheese (about 6 ounces)

Instructions (Condensed)

1. Sauté onions and shallots in oil and salt over medium–low, stirring often, until soft and golden, 30–40 minutes.
2. Stir in flour and cook 2–3 minutes. Add wine, sherry vinegar, thyme and bay leaves; simmer 10 minutes.
3. Add broth and chicken, bring to a boil, then simmer until chicken is cooked through, 25–30 minutes.
4. Remove chicken, shred, return to pot, taste and adjust seasoning. Remove herb stems and bay leaves.
5. Ladle soup into oven-safe bowls, top with toasted bread and cheese, then broil until cheese melts and bubbles, 2–3 minutes.

Notes

• If you don’t have oven-safe bowls, make cheesy croutons: arrange toasted bread on a baking sheet, season, add cheese and toast until melted, then add to individual bowls of soup.
• For a lighter version, use less cheese or choose a lower-fat Swiss alternative.

Nutrition (per serving)

Serving size: 1 ½ cups (approx.) — Calories: 437; Protein: 40 g; Carbs: 29 g; Fat: 17 g; Fiber: 4.5 g.