French Onion Soup with Sherry and Gruyère Toasts

We are in the mood for classics this month, and with the weather changing, this recipe is easy to prepare while being on the elegant end of comfort food.

Slowly caramelized onions, savory beef broth, and dry sherry give this soup its deep, rounded flavor, while a bubbling Gruyère topping makes it especially inviting. It is the perfect fall and winter meal. The Zinc House Farm store has the perfect sourdough bread, made by local purveyor Taste of Grace, for the toast topping this dish. While you’re there, pick up the sweet local onions and, of course, the wine we’ve paired below.

Clark Ferrea’s 2025 Chardonnay, Monterey County, has an oak influence that makes it a promising match for the toasted bread, nutty cheese, and caramelized onions. The winery lists it as handcrafted and “kissed by oak.”

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Recipe Information

  • Prep Time: 20 Minutes
  • Cook Time: 105 Minutes
  • Total Time: 125 Minutes
  • Serving Size: 1 crock
  • Total Servings: 6

Ingredients

Soup

  • 4 tbsp unsalted butter
  • 1 tbsp olive oil
  • 3 lb yellow onions (halved and thinly sliced)
  • ½ tsp kosher salt (plus more to taste)
  • 2 garlic cloves (minced)
  • ½ cup dry sherry (preferably dry Amontillado)
  • 8 cups good-quality, low-sodium beef stock
  • 4 fresh thyme sprigs
  • 1 bay leaf
  • 1 tsp Worcestershire sauce
  • Freshly ground black pepper
  • 1 to 2 teaspoons sherry vinegar (optional, to finish)

Topping

  • 12 sourdough slices (about 1/2 inch thick)
  • 2 cups coarsely grated Gruyère (about 8 ounces)
  • Fresh thyme leaves (optional, for garnish)

Directions

Method

  1. Caramelize the onions. Melt the butter with the olive oil in a large, heavy-bottomed Dutch oven over medium heat. Add the onions and salt; cook for about 10 minutes, stirring occasionally, until softened. Reduce the heat to medium-low and cook for 60 to 90 minutes, stirring regularly and more often toward the end, until the onions are deeply golden brown and very soft. If browned bits threaten to burn, stir in a tablespoon or two of water and scrape the bottom. Let color, rather than the clock, determine when they are ready. Slow caramelization is what builds the soup’s sweetness and depth.

  2. Add the garlic and sherry. Stir in the garlic and cook for 1 minute. Pour in the sherry, scraping up the browned bits from the bottom of the pot. Simmer for about 3 minutes, until the liquid has reduced substantially.

  3. Simmer the soup. Add the beef stock, thyme sprigs, bay leaf, Worcestershire sauce, and a few grinds of pepper. Bring to a gentle simmer and cook, partially uncovered, for 25 to 30 minutes. Remove the thyme stems and bay leaf. Taste and adjust the salt and pepper. If the broth needs a little brightness, stir in the optional sherry vinegar, 1 teaspoon at a time.

  4. Toast the bread. While the soup simmers, heat the oven to 400°F. Arrange the sourdough slices on a baking sheet and toast for 8 to 10 minutes, turning once, until crisp and lightly golden.

  5. Add the cheese topping. Switch the oven to broil. Set six broiler-safe soup crocks on a sturdy rimmed baking sheet. Ladle in the hot soup, leaving room for the topping. Place two toasts on each serving and divide the Gruyère evenly over them.

  6. Broil and serve. Broil until the cheese melts, bubbles, and browns in spots, about 2 to 4 minutes, watching closely. Garnish with thyme leaves, if desired, and serve carefully; the crocks will be very hot.

A note on the sherry

  1. Choose dry sherry rather than cream sherry. Dry Amontillado is particularly appealing here for its nutty, gently oxidative character, which complements the caramelized onions.

  2. Keep the sherry in the pot and pour the Chardonnay alongside; the two wines serve different purposes in the meal.

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