French Onion Soup

French Onion Soup is an iconic dish that brings together caramelized onions, rich broth, crusty bread, and melted Gruyère cheese for a deeply comforting, flavorful meal. This soup, perfect for chilly days or cozy dinners, delivers layers of savory goodness in every spoonful. With the sweetness of the caramelized onions and the richness of the broth, topped with crispy bread and bubbly cheese, it’s no wonder French Onion Soup has remained a beloved staple in French cuisine and beyond.

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Why You’ll Love French Onion Soup

The beauty of French Onion Soup lies in its simplicity and depth of flavor. The long caramelization process transforms humble onions into a sweet, rich base for the soup. When combined with a mix of beef and chicken broth, the result is a deeply savory and hearty broth that’s perfect for soaking into the crispy, toasted bread. The finishing touch—melted Gruyère cheese—creates a gooey, golden topping that turns this soup into a satisfying, indulgent dish.

It’s easy to see why French Onion Soup is such a popular choice in both home kitchens and restaurants. It feels like a luxurious treat but is simple enough to make for a weeknight dinner.

Ingredient Breakdown

1. Onions (4 large, thinly sliced)

Onions are the star of this dish. When slowly caramelized, they develop a deep, sweet flavor that forms the base of the soup.

• Tip: Yellow onions or a mix of yellow and sweet onions work best for the right balance of sweetness and savoriness.

2. Butter (2 tablespoons) & Olive Oil (1 tablespoon)

A combination of butter and olive oil is used to sauté the onions. The butter adds richness, while the olive oil helps prevent the butter from burning during the long caramelization process.

3. Garlic (2 cloves, minced)

Garlic adds a subtle, savory note that complements the sweetness of the caramelized onions.

4. Thyme (1 teaspoon fresh or 1/2 teaspoon dried) & Bay Leaf (1)

These herbs add an earthy depth to the soup. Thyme pairs perfectly with the onions and broth, while the bay leaf infuses the soup with a subtle aromatic flavor.

5. Beef Broth (4 cups) & Chicken Broth (1 cup)

A combination of beef and chicken broth provides a rich, savory base for the soup. The beef broth offers robust flavor, while the chicken broth adds a lighter note to balance it out.

• Tip: Use low-sodium broth so you can control the salt level as the soup simmers.

6. Dry White Wine (1/2 cup, optional)

The white wine adds a subtle acidity that cuts through the richness of the broth and balances the sweetness of the onions.

• Tip: If you prefer not to use wine, you can substitute with more broth or a splash of apple cider vinegar for a similar effect.

7. Baguette or French Bread (8 slices, toasted)

Toasted bread is an essential component of French Onion Soup, providing a crispy layer that soaks up the flavorful broth.

• Tip: Use a sturdy, crusty bread like a baguette, and toast it well to ensure it holds up under the soup and cheese.

8. Gruyère Cheese (1 1/2 cups, shredded)

Gruyère is a nutty, melty cheese that’s perfect for topping French Onion Soup. When broiled, it forms a golden, bubbly crust that makes this dish extra indulgent.

• Tip: If you can’t find Gruyère, you can substitute it with Swiss or Emmental cheese for a similar flavor and texture.

Step-by-Step Instructions for French Onion Soup

Step 1: Caramelize the Onions

In a large pot, melt 2 tablespoons of butter with 1 tablespoon of olive oil over medium heat. Add the thinly sliced onions and stir them occasionally. The key here is patience—caramelizing the onions takes 30-40 minutes, but the result is a deeply flavorful base for your soup.

• Tip: Stir the onions occasionally to prevent burning, and if they start to stick, you can add a splash of water to help deglaze the pot.

Step 2: Add Garlic and Herbs

Once the onions are golden brown and caramelized, add the minced garlic, 1 teaspoon of fresh thyme (or 1/2 teaspoon dried), and 1 bay leaf. Cook for an additional minute until the garlic becomes fragrant.

Step 3: Add Broth and Wine

Pour in 4 cups of beef broth, 1 cup of chicken broth, and 1/2 cup of dry white wine (if using). Stir to combine and bring the soup to a boil. Once it’s boiling, reduce the heat and let it simmer for 15-20 minutes to allow the flavors to meld. Season the soup with salt and pepper to taste.

• Tip: As the soup simmers, taste and adjust the seasoning. You may want to add more salt depending on your preference and the saltiness of your broth.

Step 4: Prepare the Bread and Cheese

While the soup is simmering, preheat your broiler. Toast 8 slices of baguette or French bread until they are golden and crispy. This will help the bread hold up to the broth without becoming soggy.

Step 5: Assemble the Soup

Ladle the hot soup into oven-safe bowls. Place a toasted slice of bread on top of each bowl, then generously sprinkle each one with shredded Gruyère cheese.

Step 6: Broil the Cheese

Carefully place the bowls under the broiler for 2-3 minutes, or until the cheese is melted, bubbly, and golden brown. Watch closely to avoid burning the cheese.

• Tip: If you don’t have oven-safe bowls, you can toast the bread with cheese separately and place it on top of the soup just before serving.

Step 7: Serve and Enjoy

Remove the bowls from the broiler (use oven mitts—these will be hot!) and garnish with a bit of fresh thyme or parsley if desired. Let the soup cool slightly before serving, and enjoy the rich, savory flavors of your homemade French Onion Soup.

Serving Suggestions

French Onion Soup is incredibly satisfying on its own, but here are a few ideas for side dishes and accompaniments that can round out the meal:

1. Green Salad

A light, crisp green salad with a simple vinaigrette provides a fresh contrast to the rich soup.

2. Roast Chicken

For a heartier meal, serve the soup alongside roast chicken or another protein like steak or pork chops.

3. Wine Pairing

A glass of dry white wine or a light red like Pinot Noir pairs beautifully with the flavors in French Onion Soup.

4. Cheese Plate

A small cheese plate with grapes, nuts, and crusty bread is a lovely accompaniment to this classic French dish.

Customizing Your French Onion Soup

This traditional French Onion Soup recipe is delicious as is, but you can customize it to suit your tastes:

1. Vegetarian Version

For a vegetarian version, simply replace the beef and chicken broths with vegetable broth. You can still achieve deep, rich flavors by caramelizing the onions well and perhaps adding a splash of balsamic vinegar or soy sauce for extra umami.

2. Adding Meat

If you want to make the soup heartier, you can add sliced sausages or pieces of roast beef. These additions will create a more substantial meal, perfect for a cold winter evening.

3. Cheese Alternatives

If Gruyère isn’t your favorite, try using other cheeses like Provolone, Swiss, or a sharp Cheddar. Each will provide a slightly different flavor profile.

Conclusion

French Onion Soup is a beloved classic that combines deeply caramelized onions with rich broth, toasted bread, and gooey cheese. The result is a warm, hearty, and flavorful dish that’s perfect for any occasion, from a casual family dinner to a special meal for guests. With simple ingredients and a little patience, you can recreate this comforting restaurant favorite at home.

So, grab your onions, broth, and cheese, and get ready to enjoy a bowl of savory goodness that’s sure to warm your heart and soul!