Classic French Three-Onion Soup

When the temperature dips or your soul craves something warm and deeply satisfying, few dishes hit the spot like a classic bowl of French onion soup. This updated version, French Three Onion Soup, uses a trio of alliums yellow onions, shallots, and leeks to add layers of sweetness and depth. Topped with a whole-wheat baguette slice and melted Gruyère, it’s everything you love about the original, with a little extra comfort built in.

Why Three Onions Are Better Than One

Traditional French onion soup typically leans heavily on caramelized yellow onions. But combining onions with shallots and leeks transforms the base into something more nuanced and flavorful. Here’s why it works:

• Yellow onions bring earthy sweetness.

• Shallots add delicate, slightly garlicky complexity.

• Leeks contribute a soft, mellow richness.

Together, they build a foundation that’s heartier, richer, and more balanced without needing excessive amounts of butter or cheese.

Key Nutritional Highlights

• Using whole-wheat baguette adds fiber and more nutrients than traditional white bread.

• Swapping some of the beef broth for water keeps sodium levels in check.

• A modest amount of Gruyère still provides that classic French flavor without overwhelming the dish with saturated fat.

Each serving delivers cozy satisfaction while staying mindful of both flavor and nutrition.

Ingredients You'll Need

• 1 tbsp unsalted butter

• 1 tsp extra-virgin olive oil

• 1½ lbs yellow onions, thinly sliced (about 6 cups)

• 6 shallots, thinly sliced (about 1¾ cups)

• 1 leek (white and light green part only), thinly sliced and washed

• Kosher salt and freshly ground black pepper

• 3–4 sprigs fresh thyme

• 1 sprig fresh rosemary

• 1 tbsp all-purpose flour

• 4 cups low-sodium beef broth

• 2 cups water

• 2 tsp Worcestershire sauce

• ¼ cup dry sherry

• 8 slices (¼-inch thick) whole-wheat baguette (about 2 oz), toasted

• ½ cup finely grated Gruyère cheese (about 1¾ oz)

• 1 tbsp chopped fresh chives

Step-by-Step Instructions

1. Sauté the onions: In a large Dutch oven, heat butter and olive oil over medium. Add yellow onions, shallots, and leeks. Season with salt and pepper. Cover and cook without stirring for 10–15 minutes until soft and lightly browned.

2. Caramelize: Uncover and continue cooking for 25–30 minutes, stirring often, until deeply golden. If the onions stick, add 1 tbsp of water to loosen.

3. Add flour and broth: Sprinkle flour over the onions and stir for 2–3 minutes to cook off the raw flour taste. Add broth and water, scraping the bottom of the pan. Tie thyme, rosemary, and the reserved leek top into a bundle and add it to the pot.

4. Simmer: Reduce heat and simmer for 20–25 minutes until slightly thickened. Stir in Worcestershire sauce, remove from heat, discard herb bundle, and add sherry. Adjust seasoning as needed.

5. Broil and serve: Preheat the broiler. Ladle soup into 4 oven-safe bowls. Top each with 2 baguette slices and a sprinkle of Gruyère. Broil until cheese melts and is golden brown about 1 minute. Garnish with fresh chives.

Serving Suggestion

Turn this rich, savory soup into a complete meal by pairing it with a simple salad: baby greens, sliced endive, and roasted beets tossed in lemon vinaigrette add freshness and brightness that complement the soup’s deep flavors.

Why It’s Worth the Effort

Though it takes some time to caramelize the onions properly, the flavor payoff is undeniable. And with thoughtful ingredient swaps and the added complexity from three types of onions, this version delivers both comfort and nourishment in a single bowl.

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