French Onion Soup the Cook's Illustrated Way

Discover the ultimate comfort food with "French Onion Soup the Cook's Illustrated Way," a deeply flavorful, restaurant-quality soup crafted with meticulous attention to detail. This recipe stands out by using a unique oven-caramelizing technique to achieve perfectly golden and richly sweet onions with minimal stirring. Infused with layers of flavor from dry sherry, a blend of chicken and beef broths, and aromatic thyme, this traditional French favorite gets an irresistible boost of depth. Finished with crusty baguette slices and a bubbling layer of shredded Gruyère cheese, this hearty soup is as satisfying as it is elegant. Perfect for cozy dinners or entertaining guests, this slow-cooked classic is a must-try for soup enthusiasts.

Nutriscore Rating: 72/100

Prep Time:20 mins

Cook Time:240 mins

Total Time:260 mins

Servings: 6

Ingredients

• 3 tablespoons butter
• 6 pounds yellow onions, sliced thinly
• 0.5 teaspoons salt
• 0.25 cup water
• 0.5 cup dry sherry
• 3 cups low-sodium chicken broth
• 2 cups beef broth
• 2 sprigs of fresh thyme
• 1 bay leaf
• 1 baguette, sliced into 1-inch thick rounds
• 2 cups Gruyère cheese, shredded
• 0.5 teaspoons sugar (optional, for boosting sweetness)

Directions

Step 1

Preheat your oven to 400°F (200°C) and adjust the oven rack to the lower-middle position.

Step 2

In a large Dutch oven, melt the butter over medium heat. Add the sliced onions and salt. Stir to coat the onions with butter.

Step 3

Place the Dutch oven, uncovered, in the preheated oven. Cook for 1 hour, stirring every 30 minutes, until the onions are significantly softened and begin to brown around the edges.

Step 4

Remove the Dutch oven from the oven and transfer it to the stovetop over medium-high heat. Cook the onions, stirring often and scraping up browned bits, until they turn deeply caramelized and sticky, about 15-20 minutes.

Step 5

Add 1/4 cup of water to the pot to deglaze, scraping up any browned bits from the bottom. Repeat the deglazing process two more times until the onions are a rich, dark brown.

Step 6

Stir in the dry sherry and cook until almost entirely evaporated, about 1-2 minutes.

Step 7

Add the chicken broth, beef broth, thyme sprigs, and bay leaf to the pot. Bring the soup to a simmer, reduce the heat to low, and simmer gently for 30 minutes. Discard the thyme sprigs and bay leaf. Taste and season with additional salt if needed.

Step 8

While the soup is simmering, preheat the broiler. Arrange the baguette slices on a baking sheet and broil until lightly toasted, 1-2 minutes per side.

Step 9

Ladle the soup into oven-safe bowls. Place 1-2 toasted baguette slices on top of each bowl, then cover with shredded Gruyère cheese. Place the bowls on a baking sheet and broil until the cheese is melted and bubbling, 3-5 minutes.

Step 10

Carefully remove the soup bowls from the oven. Let cool slightly before serving.

Nutrition Facts

Serving size	(4404.3g)

Amount per serving	% Daily Value*
Calories	2588.4

Total Fat 112.3g	0%
Saturated Fat 60.3g	0%
Polyunsaturated Fat 1.1g
Cholesterol 338.7mg	0%
Sodium 5262.6mg	0%
Total Carbohydrate 280.7g	0%
Dietary Fiber 47.5g	0%
Total Sugars 121.7g
Protein 108.8g	0%

Vitamin D 54.7IU	0%
Calcium 2851.5mg	0%
Iron 8.3mg	0%
Potassium 4487.2mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 39.3%

Protein: 16.9%

Carbs: 43.7%