Why You’ll Love This Recipe

French Onion Soup is a rich, deeply flavorful classic featuring caramelized onions simmered in a savory broth, topped with toasted bread and melted, bubbly cheese. Elegant yet comforting, this timeless dish is perfect for cozy dinners, special occasions, or any time you crave something hearty and delicious.

ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
yellow onions (thinly sliced)butterolive oilbeef broth (or a mix of beef and chicken broth)dry white wineflourgarlic clovesbay leaffresh thymebalsamic vinegar or Worcestershire saucesaltblack pepperbaguette slicesgruyère cheese (or Swiss cheese)

directions

Heat butter and olive oil in a large pot over medium-low heat.

Add sliced onions and cook slowly, stirring frequently, until deeply caramelized and golden brown (about 40-45 minutes).

Stir in minced garlic and cook for another minute.

Sprinkle flour over the onions and stir well to coat.

Add white wine to deglaze the pot, scraping up any brown bits.

Pour in beef broth, add bay leaf, thyme, balsamic vinegar, salt, and pepper.

Bring to a simmer and cook for 20-25 minutes to develop flavor.

Toast baguette slices under the broiler until crisp.

Ladle the soup into oven-safe bowls, top each with a toasted baguette slice and generous amounts of gruyère cheese.

Place bowls under the broiler until the cheese is melted, bubbly, and golden.

Servings and timing

This recipe yields approximately 4 servings.
Preparation time: 15 minutes
Caramelizing time: 40-45 minutes
Simmering and broiling time: 30 minutes
Total time: 1 hour 30 minutes

Variations

Use a mix of onions like sweet and red for deeper flavor.
Add a splash of brandy or sherry with the wine for richness.
Use provolone or mozzarella if gruyère is unavailable.
Top with extra thyme or a sprinkle of Parmesan for an herby twist.

storage/reheating

Store leftover soup (without the bread and cheese topping) in an airtight container in the refrigerator for up to 4 days.
Reheat gently on the stovetop and assemble with fresh toast and cheese before serving.
Freeze the soup base for up to 3 months; thaw overnight in the fridge before reheating.

FAQs

Can I make it without wine?
Yes, replace it with extra broth or a splash of balsamic vinegar.

What’s the best onion to use?
Yellow onions are traditional, but a mix can enhance the flavor.

Can I prepare it ahead?
Yes, the soup base gets even better after a day in the fridge.

Is it vegetarian?
Use vegetable broth and check the cheese if you need a vegetarian version.

Can I skip the flour?
Yes, but the flour adds body to the broth.

What bread works best?
A crusty French baguette holds up perfectly.

What cheese is closest to gruyère?
Swiss or Emmental are good substitutes.

Is this soup gluten-free?
Use gluten-free bread and skip the flour or use gluten-free flour.

Can I make it in a slow cooker?
You can caramelize the onions first, then finish the soup in a slow cooker.

Can I freeze the whole assembled soup?
Freeze the base only; add fresh bread and cheese after reheating.

Conclusion

French Onion Soup is an irresistible classic that combines sweet, savory, and cheesy flavors into one perfect bowl. Whether served as a starter or the star of the meal, this timeless recipe brings a touch of rustic elegance and unbeatable comfort to your table!