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Benjamin

Best French Onion Soup Gratinée for Comfort Food Lovers

Warm up with a bowl of rich and comforting French Onion Soup Gratinée, a classic French dish that’s both elegant and hearty. Sweet caramelized onions simmered in a flavorful broth are topped with crusty French bread and melted, golden cheese. Each spoonful is an indulgent combination of savory, cheesy, and slightly sweet flavors. Perfect for chilly nights or when you want to bring a bit of French bistro flair to your table, this recipe is easy to follow and always impressive!
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Prep Time 10 minutes
Cook Time 1 hour 15 minutes
Total Time 1 hour 25 minutes
Servings: 4 servings
Course: Soup
Cuisine: French
Ingredients Method Notes

Ingredients
  

For the Soup
  • 4 tablespoons butter
  • 2 large red onions thinly sliced
  • 2 large sweet onions thinly sliced
  • 1 teaspoon salt
  • 1 48-ounce can chicken broth
  • 1 14-ounce can beef broth
  • 1/2 cup red wine
  • 1 tablespoon Worcestershire sauce
  • 2 sprigs fresh parsley
  • 1 sprig fresh thyme leaves
  • 1 bay leaf
  • 1 tablespoon balsamic vinegar
  • Salt and freshly ground black pepper to taste
For the Topping
  • 4 thick slices French bread
  • 8 slices Gruyère cheese at room temperature
  • 1/2 cup shredded Asiago cheese at room temperature
  • 4 pinches paprika

Method
 

Step 1: Caramelize the Onions
  1. Melt the butter in a large pot over medium-high heat.
  2. Add the sliced red and sweet onions and sprinkle with 1 teaspoon of salt.
  3. Cook, stirring frequently, for about 35 minutes, or until the onions are deeply caramelized and syrupy. Take your time here—this is where the soup gets its rich flavor!
Step 2: Simmer the Broth
  1. Add the chicken broth, beef broth, red wine, and Worcestershire sauce to the pot.
  2. Tie the parsley, thyme, and bay leaf together with kitchen twine to form an herb bundle. Add it to the soup.
  3. Bring the soup to a gentle simmer over medium heat and cook for 20 minutes, stirring occasionally.
  4. Remove and discard the herb bundle.
  5. Stir in the balsamic vinegar and season with salt and freshly ground black pepper to taste. Keep the soup warm over low heat while you prepare the bread topping.
Step 3: Toast the Bread
  1. Preheat the broiler and set an oven rack about 6 inches from the heat source.
  2. Arrange the French bread slices on a baking sheet.
  3. Broil for about 3 minutes per side, or until the bread is golden and crisp. Remove from the oven but leave the broiler on.
Step 4: Assemble the Bowls
  1. Place 4 oven-safe bowls or crocks on a rimmed baking sheet for easy handling.
  2. Fill each bowl about two-thirds full with the hot onion soup.
  3. Place one slice of toasted bread on top of the soup in each bowl.
  4. Lay two slices of Gruyère cheese over the bread, and sprinkle 1/4 of the shredded Asiago cheese on top.
  5. Add a pinch of paprika to each bowl for a pop of color and flavor.
Step 5: Broil the Topping
  1. Place the baking sheet with the bowls under the broiler.
  2. Broil for about 5 minutes, or until the cheese is bubbly, golden brown, and cascading over the edges of the bowls. Watch closely to avoid burning.
Step 6: Serve and Enjoy
  1. Carefully remove the bowls from the oven (they’ll be very hot!) and let them cool slightly.
  2. Serve immediately and enjoy this deliciously cheesy and comforting soup.

Notes

  • Make-Ahead Option: You can make the soup base a day ahead and store it in the refrigerator. Reheat on the stovetop before assembling and broiling.
  • Herb Substitutes: If you don’t have fresh parsley or thyme, use 1/2 teaspoon of dried parsley and thyme instead.
  • Cheese Alternatives: Gruyère and Asiago are traditional, but Swiss, Emmental, or mozzarella are excellent substitutes.
  • Serving Suggestion: Pair the soup with a crisp green salad or a glass of dry red wine for a complete meal.
  • Storage: Store leftover soup in an airtight container in the refrigerator for up to 3 days. The cheese and bread topping should be added fresh when reheating.

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