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BEST French Onion Soup Recipe – Rich, Cozy & Comforting

This French Onion Soup is a timeless classic that delivers everything you crave in a comforting bowl — deep caramelized onions, rich savory broth, golden melted cheese, and warm toasty bread that soaks up every bit of flavor. While traditional French onion soup often includes wine, this recipe stays completely alcohol-free while still achieving that iconic depth and complexity through slow caramelization and richly seasoned broth. Each spoonful is warm, silky, and packed with the natural sweetness of onions that have been slowly cooked until golden and jam-like. The broth absorbs all the savory notes from the onions, thyme, and butter, creating a beautifully layered dish that tastes indulgent without requiring complicated techniques. Whether you're serving this as a cozy dinner, a starter for guests, or a comforting treat on a cold night, this nourishing bowl of French Onion Soup brings restaurant-level flavor right to your kitchen — easily and affordably. Get ready for a heart-hugging soup that feels gourmet, elegant, and deeply satisfying.
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Prep Time 10 minutes
Cook Time 1 hour
Total Time 1 hour 10 minutes
Servings: 4 servings
Ingredients Equipment Method Notes

Ingredients
  

Soup Base
  • 5 –6 large yellow onions thinly sliced
  • 4 tbsp unsalted butter
  • 2 tbsp olive oil
  • 4 cups beef broth or chicken broth if preferred
  • 2 cups vegetable broth
  • 2 –3 fresh thyme sprigs or 1 tsp dried thyme
  • 2 bay leaves
  • Salt and black pepper to taste
Toasted Bread
  • 4 slices of crusty bread or baguette toasted
Cheese Topping
  • 1 cup shredded Gruyère cheese
  • 1 cup shredded mozzarella or provolone

Equipment

  • Large heavy pot or Dutch oven
  • Wooden spoon
  • Cutting board
  • Sharp knife
  • Oven-safe soup bowls
  • Baking sheet
  • Ladle

Method
 

Step 1: Caramelize the onions
  1. Heat butter and olive oil in a large Dutch oven over medium heat.
  2. Add sliced onions and stir well to coat.
  3. Cook for 30–40 minutes, stirring occasionally, until the onions become deeply caramelized, golden brown, and sweet.
  4. This is the foundation of the soup — take your time.
Step 2: Season and build flavor
  1. Add thyme, bay leaves, salt, and pepper.
  2. Stir and cook for another 2 minutes.
Step 3: Add the broth
  1. Pour in beef broth and vegetable broth.
  2. Stir to combine and bring the soup to a gentle simmer.
Step 4: Simmer
  1. Reduce heat to low and simmer for 20–25 minutes, allowing the flavors to deepen and blend.
Step 5: Prep the bread
  1. While the soup simmers, toast the slices of bread until golden and crisp.
  2. This helps them stay firm when topped with cheese and added to the soup.
Step 6: Assemble
  1. Ladle hot soup into oven-safe bowls.
  2. Place one toasted bread slice on top of each bowl.
  3. Sprinkle generously with Gruyère and mozzarella.
Step 7: Broil
  1. Place bowls onto a baking sheet and broil for 2–3 minutes or until the cheese is melted, bubbly, and lightly golden.
Step 8: Serve
  1. Carefully remove from the oven and serve immediately.

Notes

🧊 Storage & Reheating
Refrigerator
Store soup (without bread) for 4 days.
Freezer
Freeze onion broth for 2 months.
Bread + cheese should be added fresh.
Reheating
Warm on the stove and re-toast bread with cheese for best results.
🥄 Variations
Extra cheesy: Increase Gruyère for a richer top.
Chicken-based: Use chicken broth instead of beef.
Vegetarian: Use all vegetable broth.
Low-salt: Reduce added salt and use low-sodium broths.
Herb twist: Add rosemary or parsley.
Sweeter profile: Add a pinch of brown sugar to onions.
Thicker soup: Blend ½ cup of caramelized onions into the broth.
Gluten-free: Use gluten-free bread.
Lighter version: Reduce butter and oil by half.
Deep caramel flavor: Cook onions for up to 50 minutes.
❓ 10 FAQs
1. Does French onion soup need wine?
No — caramelized onions alone create incredible depth.
2. Can I use red onions?
Yellow onions work best, but white or sweet onions also work.
3. Can I use only one type of broth?
Yes — just use a total of 6 cups.
4. Why did my onions burn?
Heat was too high; keep it low and stir often.
5. Can I skip the cheese topping?
Yes, but it’s part of the classic experience.
6. What cheese melts best?
Gruyère is traditional; mozzarella adds stretchiness.
7. Can I make this ahead?
Yes — caramelized onions taste even better the next day.
8. How do I thicken the soup?
Simmer longer, or blend a small portion.
9. What bread is best?
Crusty baguette slices hold up beautifully.
10. Can I make this dairy-free?
Use olive oil instead of butter and omit the cheese.
🏁 Conclusion
This BEST French Onion Soup is the definition of warm, cozy comfort. With deeply caramelized onions, rich broth, and that iconic cheesy bread topping, every bowl feels like a comforting restaurant-style experience made right at home. It’s simple, elegant, budget-friendly, and incredibly satisfying — perfect for chilly nights, dinner parties, or anytime you crave something deeply flavorful.