French Onion Soup (Soupe à l'Oignon Gratinée) Recipe

4 servings


2 hours

total time


6 tablespoons (90g) unsalted butter, plus more for bread

3 pounds (1.4kg) yellow or mixed onions, sliced 1/8 inch thick (see note)

Kosher salt and freshly ground black pepper

1/2 cup (120ml) dry sherry (such as Amontillado)

2 quarts (1.8L) homemade or store-bought low-sodium chicken stock

2 sprigs thyme

1 bay leaf

1 teaspoon (5ml) Asian fish sauce (optional)

1 teaspoon (5ml) cider vinegar

8 bowl-size slices rustic bread, toasted until crisp

1 medium clove garlic

1 pound (450g) Gruyère cheese, grated

Freshly minced chives, for garnish


In a large stainless steel saucepan, or in 2 large stainless steel or cast iron skillets, melt butter over medium-high heat until foaming. Add onions and cook, stirring occasionally, until softened, about 8 minutes. Lower heat to medium-low and cook, stirring frequently, until onions are very sweet and a rich golden-brown color, 1 to 2 hours. If browned onion juices on bottom of pot threaten to burn, add 1 tablespoon (15ml) water, scrape up browned bits, and continue cooking. Season with salt and pepper.

Add sherry and bring to a simmer, scraping up any browned bits. (If using 2 skillets, divide sherry between them, then scrape onions and liquid from both pans into a pot or Dutch oven to continue.) Cook until alcohol smell is mostly gone, about 3 minutes. Add stock, thyme, and bay leaf; raise heat to medium-high; and bring to a simmer. Lower heat and simmer for 20 minutes.

Add fish sauce, if using, and cider vinegar. Season with salt and pepper. Discard thyme sprigs and bay leaf.

Preheat broiler and adjust oven rack to top position. Butter toasts and rub with garlic clove until fragrant. Spoon a small amount of broth into the bottoms of 4 ovenproof serving bowls, then top with half the toasts. Sprinkle some grated cheese on top of toasts, then spoon more soup and onions on top, nearly filling bowls. Set remaining 4 toasts in bowls, pushing to nearly submerge them. Top with remaining grated cheese and set bowls on a rimmed baking sheet. Broil until cheese is melted and browned in spots. Garnish with chives and serve.


Serving Size

Serves 4


1011 kcal

Total Fat

59 g

Saturated Fat

34 g

Unsaturated Fat

0 g

Trans Fat



178 mg


2560 mg

Total Carbohydrate

71 g

Dietary Fiber

6 g

Total Sugars

21 g


52 g

4 servings


2 hours

total time
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