Classic French Onion Soup

A classic French Onion Soup is the hallmark of bistro comfort, turning humble yellow onions into a rich, deep, and savory masterpiece. Slow-cooked caramelization creates a base that is both sweet and complex, perfectly balanced by a robust beef broth and a crown of melted, bubbling cheese.

Bookmark

Whether you are looking for a cozy weeknight dinner or an impressive starter for a dinner party, this soup delivers the warm, hearty satisfaction that only a time-tested recipe can provide.

Ingredients

• 6 large yellow onions, thinly sliced
• 2 tablespoons unsalted butter
• 1 tablespoon olive oil
• 6 cups beef broth (substitute with vegetable broth for vegetarian)
• 1/2 cup dry white wine (optional)
• 2 cloves garlic, minced
• 1 teaspoon sugar
• 1 teaspoon salt
• 1/2 teaspoon freshly ground black pepper
• 2 sprigs fresh thyme (or 1/2 teaspoon dried thyme)
• 1 bay leaf
• 4 slices crusty French bread (about 1 inch thick)
• 2 cups grated Gruyère cheese

Instructions

Step 1: Soften the Onions

In a large heavy-bottomed pot, melt the butter with the olive oil over medium heat. Add the sliced onions and cook, stirring occasionally, until softened (about 15 minutes).

Step 2: Caramelize

Sprinkle the onions with sugar and salt. Continue to cook, stirring frequently, until the onions are deeply golden and caramelized (about 30–40 minutes).

Step 3: Aromatics

Add the minced garlic and cook for 1 minute more.

Step 4: Deglaze

Pour in the white wine (if using) and scrape up any browned bits from the bottom of the pot. Simmer for 2–3 minutes.

Step 5: Simmer the Broth

Add the beef broth, thyme, bay leaf, and black pepper. Bring to a boil, then reduce heat and simmer uncovered for 30 minutes. Remove and discard the thyme sprigs and bay leaf.

Step 6: Toast the Bread

Preheat the broiler. Arrange the bread slices on a baking sheet and toast under the broiler until lightly golden on both sides.

Step 7: Assemble

Ladle the hot soup into oven-safe bowls. Top each with a slice of toasted bread and a generous handful of Gruyère cheese.

Step 8: Broil and Serve

Place the bowls under the broiler until the cheese is melted and bubbling, 2–3 minutes. Serve immediately.

Zusatztipps für die Zubereitung

For an extra layer of flavor, try rubbing the toasted bread slices with a cut clove of garlic before placing them on top of the soup. This subtle touch infuses the bread with a wonderful aroma that complements the broth perfectly.

Varianten und Anpassungen

To make this dish vegetarian, simply substitute the beef broth with a high-quality vegetable broth. If you cannot find Gruyère, Emmental or Swiss cheese make excellent alternatives that melt beautifully over the crusty bread.

Serviervorschläge

This bistro classic pairs beautifully with a glass of dry white wine or a light-bodied red. Serve it as a substantial main course or as a decadent starter for a French-themed evening.

Bookmark

Enjoy this timeless French favorite immediately while the cheese is at its peak of melted perfection. It is a soul-warming dish that never goes out of style.

Recipe Questions

→ How long does it take to properly caramelize onions?

Properly caramelizing onions takes 30-40 minutes over medium heat with frequent stirring. The sugar helps develop deep golden color and sweet flavor.

→ Can I make this vegetarian?

Yes, simply substitute vegetable broth for the beef broth. The caramelized onions still provide rich, deep flavor.

→ What cheese works best if I can't find Gruyère?

Emmental or Swiss cheese are excellent alternatives. They melt beautifully and provide similar nutty, savory flavor.

→ Do I need oven-safe bowls?

Yes, oven-safe bowls are essential for broiling the cheese topping. Traditional French onion soup crocks work perfectly.

→ Can I prepare this ahead of time?

The soup base can be made 2-3 days ahead and refrigerated. Add bread and cheese just before serving and broil fresh.

→ Why add sugar to the onions?

Sugar accelerates caramelization and helps develop the rich, golden color and sweet depth of flavor characteristic of this dish.