Classic French Onion Soup

If you’re looking for a rich, comforting, and deeply flavorful soup, this Classic French Onion Soup is a must-try! With caramelized onions, a savory broth, and a cheesy, golden-brown topping, this dish is the perfect way to warm up on a chilly day.

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Why You’ll Love This Recipe

• Deep, Savory Flavor: Slow-cooked onions bring out a rich sweetness that pairs perfectly with a flavorful broth.
• Cheesy, Crispy Topping: The combination of toasted bread and melted cheese makes every bite irresistible.
• Restaurant-Quality at Home: Impress your family with this classic bistro favorite!

Ingredients You’ll Need

For the Soup:

• Yellow Onions (4 large, thinly sliced) – The star ingredient, caramelized to perfection.
• Butter (2 tbsp) – Adds richness to the onions.
• Olive Oil (1 tbsp) – Helps prevent the butter from burning.
• Garlic (2 cloves, minced) – Enhances the depth of flavor.
• Beef Broth (6 cups) – A rich base for the soup.
• Bay Leaf (1) – Infuses the soup with a subtle herbal note.
• Fresh Thyme (2 sprigs, or ½ tsp dried thyme) – Adds warmth and complexity.
• Salt & Black Pepper (to taste) – Brings out the flavors.
• Sugar (½ tsp, optional) – Helps speed up caramelization.
• Balsamic Vinegar (1 tbsp) – Balances the sweetness of the onions with a hint of acidity.

For the Topping:

• French Baguette (6 slices, toasted) – Provides the perfect crunchy base.
• Gruyère Cheese (1 ½ cups, shredded) – Melts beautifully for that golden, bubbly topping.
• Parmesan Cheese (¼ cup, grated) – Adds extra savory depth.

Tools You’ll Need

• Large heavy-bottomed pot or Dutch oven
• Wooden spoon for stirring
• Oven-safe soup bowls
• Baking sheet

How to Make Classic French Onion Soup

Step 1: Caramelize the Onions

1. Heat butter and olive oil in a large pot over medium-low heat.
2. Add sliced onions and cook, stirring occasionally, until they turn deep golden brown, about 40–50 minutes. If they start to burn, lower the heat.
3. Stir in garlic, salt, pepper, and sugar (if using). Cook for another 2 minutes.
4. Add balsamic vinegar, stirring to deglaze the pan and enhance the flavors.

Step 2: Make the Soup Base

5. Pour in beef broth and add the bay leaf and thyme.
6. Bring to a simmer and let it cook for 20–30 minutes, allowing the flavors to meld.
7. Remove the bay leaf and thyme sprigs before serving.

Step 3: Prepare the Topping

8. While the soup simmers, preheat the oven to 375°F (190°C).
9. Place baguette slices on a baking sheet and toast them until golden, about 5 minutes.

Step 4: Assemble and Broil

10. Ladle the hot soup into oven-safe bowls.
11. Place a toasted baguette slice on top of each bowl.
12. Sprinkle generously with Gruyère and Parmesan cheese.
13. Place the bowls under the broiler for 2–3 minutes, or until the cheese is melted and golden brown.

Step 5: Serve and Enjoy!

14. Carefully remove from the oven (bowls will be hot!). Let cool slightly, then dig in and enjoy the rich, cheesy goodness.

What to Serve with French Onion Soup

• A fresh green salad with a light vinaigrette.
• A side of roasted vegetables or sautéed mushrooms.
• Extra toasted baguette slices for dipping.

Tips for the Best French Onion Soup

• Be Patient with the Onions: Slow caramelization is key to getting that deep, sweet flavor.
• Use Good-Quality Cheese: Gruyère is the classic choice, but Swiss or provolone can also work.
• Broil with Caution: Keep an eye on the cheese to prevent burning.

Storing and Reheating

• Refrigerate: Store leftovers in an airtight container for up to 3 days.
• Freeze: The soup (without the bread and cheese) can be frozen for up to 3 months.
• Reheat: Warm the soup on the stovetop and broil fresh bread and cheese before serving.

Frequently Asked Questions

Can I make this vegetarian?
Yes! Swap the beef broth for vegetable broth for a delicious meat-free version.

What if I don’t have oven-safe bowls?
You can melt the cheese on the bread slices separately under the broiler, then place them on top of the soup before serving.

Can I use a different cheese?
Absolutely! Mozzarella, Swiss, or even sharp cheddar can work if you don’t have Gruyère.

Conclusion

This Classic French Onion Soup is the ultimate cozy meal, packed with rich caramelized onions, savory broth, and that irresistible cheesy topping. Whether you’re serving it as a starter or a main dish, it’s sure to impress!

Don’t forget to leave a review below and share your photos on Pinterest! I can’t wait to see how your dish turns out.

Preparation Time: 15 minutes
Cooking Time: 1 hour
Cuisine: French

Nutritional Information (Per Serving):
Calories: 320 | Protein: 12g | Carbohydrates: 35g | Fat: 15g | Fiber: 3g | Sodium: 780mg

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