February 25, 2020

French Onion Soup With Grilled Gruyère Sandwiches

Recipe: Melissa Clark

Try this French Onion Soup With Grilled Gruyère Sandwiches recipe from the new cookbook, Dinner in French.

The French may have their gratinéed onion soup with croutons and Gruyère melted on top, but our American tradition of tomato soup with grilled cheese sandwiches for dunking offers similar warming, cheese-oozing pleasures. This recipe merges elements from each dish. The broth (preferably homemade) is full of deeply caramelized onions, but the Gruyère is layered, along with more caramelized onions, onto bread and fried into sandwiches to serve on the side. This hybrid is a bit easier to serve than classic French onion soup because you don’t need to broil the individual bowls just before serving. And with all that dunking, I think it’s a lot more fun to eat, too.


For The Soup

  • 1 bay leaf
  • 6 sprigs fresh thyme
  • 8 tbsp (1 stick) unsalted butter
  • 3 lbs. onions, thinly sliced
  • 2 tsp fine sea salt, divided
  • ¾ cup brandy
  • 2 tbsp Port, Madeira or sweet Marsala
  • 2 cups dry white wine
  • 4 cups beef stock, preferably homemade
  • 4 cups chicken stock, preferably homemade
  • ½ tsp freshly ground black pepper
  • Chopped fresh parsley leaves, for serving

For The Grilled Cheese

  • 1 tbsp unsalted butter, plus more for the bread, room temperature
  • 4 slices white or whole-wheat sandwich bread
  • Dijon mustard, for spreading (optional)
  • 1 cup (4 oz) grated Gruyère cheese


Yield: Serves 4 to 6

Thinking Ahead

Soup: You can make the soup one week in advance. Store it, covered, in the refrigerator.
Onions: You can store the reserved cooked onions for the sandwiches, covered, in the refrigerator for up to one week.

Make The Soup

  1. Make a bouquet garni by tying the bay leaf and thyme sprigs together with kitchen twine (or skip this step and just throw the herbs directly into the pot with the onions in step 2, though you’ll have to fish them out later).
  2. In a large heavy soup pot or Dutch oven, melt the butter over low heat. Stir in the onions and bouquet garni and cover the pot. Cook for 30 minutes, then uncover the pot and raise the heat to medium-high. Cook, sautéing, until the onions are caramelized and golden, 25 to 35 minutes longer. If the onions start to burn, reduce the heat. You are looking for soft, evenly golden onions without dark brown spots.
  3. Stir in 1 teaspoon of the salt, the brandy and Port (be careful, it may flame up). Scrape up any browned bits stuck to the bottom of the pot, and cook until the liquid has been absorbed, three to five minutes. Remove ⅓ cup of the cooked onions and reserve it for the sandwiches.
  4. Stir the wine, beef stock, chicken stock and pepper into the soup pot. Simmer for one hour, skimming off any large pockets of foam that form from time to time. Remove the bouquet garni or loose herbs, taste the soup and add one more teaspoon salt, or to taste (this will depend on how salty your stock was to start).

Make The Grilled Cheese

  1. In the last 10 minutes of the soup’s cooking time, butter both sides of each slice of bread. Then, if you are using it, spread the mustard over the butter on one side of each slice. Heap half of the reserved onions, and then half of the Gruyère, on the mustard side of 2 bread pieces. Top with the remaining 2 pieces of bread (mustard side facing the cheese) and press down firmly with a spatula. The plain buttered sides should be on the outside of the sandwiches.
  2. Heat the one tablespoon butter in a large nonstick skillet over medium-low heat. When the butter is hot, place both sandwiches in the skillet, cover and cook for three to four minutes, until the underside is golden. Flip them over and cook the other side for about another three minutes, until the bread is golden and the cheese is molten.
  3. To serve, ladle the soup into serving bowls and sprinkle each serving with parsley. Cut the sandwiches in fourths and serve them alongside the soup for dunking, or float the sandwiches on top of the soup.

Excerpted from Dinner in French: My Recipes by Way of France by Melissa Clark. Copyright © 2020 by Melissa Clark. Published in the United States by Clarkson Potter/Publishers, an imprint of the Crown Publishing Group, a division of Penguin Random House LLC, New York. Reproduced by arrangement with the Publisher. All rights reserved.