French Onion Soup Gratinée

Looking for the best French onion soup recipe? This rich and tasty, cheese-topped onion gratinée soup recipe is about as good as it gets!

• Preparation Time: 15 mins
• Cooking Time: 60 mins
• Total Time: 1 hr 15 mins
• Calories: 618 Calories

Ingredients

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

Recipe Instructions

Step 1

Melt butter in a large pot over medium-high heat. Stir in red onions, sweet onions, and salt. Cook, stirring frequently, until onions are caramelized and almost syrupy, about 35 minutes.

Step 2

Stir in chicken broth, beef broth, red wine, and Worcestershire sauce. Bundle parsley, thyme, and bay leaf with kitchen twine; add to the pot. Simmer over medium heat for 20 minutes, stirring occasionally. Remove and discard herb bundle. Reduce heat to low; stir in vinegar and season with salt and pepper. Cover soup and keep warm over low heat while you prepare the toast.

Step 3

Arrange 4 large oven-safe bowls or crocks on a rimmed baking sheet. Fill each bowl 2/3 full with hot soup. Top each bowl with 1 slice of toasted bread, 2 slices Gruyère cheese, and 1/4 of the Asiago cheese. Sprinkle a little bit of paprika over the top of each one.

Step 4

Cook under the hot broiler until bubbly and golden brown, about 5 minutes. Cheese will cascade over the sides of the crock and form a beautifully melted crusty seal as it melts.

Step 5

Set an oven rack about 6 inches from the heat source and preheat the oven's broiler. Arrange bread slices on a baking sheet and broil, turning once, until well toasted on both sides, about 3 minutes. Remove from heat; do not turn off the broiler.

Step 6

Serve hot and enjoy!