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Classic French Onion Soup
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Course Soup
Cuisine French
Servings 4 people

Equipment

  • Slow Cooker
  • Large Skillet
  • Baking Sheet

Ingredients
  

  • 5 large yellow onions, thinly sliced
  • 3 tablespoons unsalted butter
  • 6 cups beef broth
  • 1 teaspoon Worcestershire sauce
  • 1/2 teaspoon dried thyme
  • Salt and black pepper to taste
  • 4 thick slices of baguette
  • 1 1/2 cups shredded Gruyere cheese

Instructions
 

  • Place the butter in a large skillet over medium heat. Add the sliced onions and cook, stirring now and then, until the onions turn golden brown and soft, about 20 minutes.
  • Transfer the cooked onions to the slow cooker. Pour in the beef broth, Worcestershire sauce, thyme, salt, and pepper. Stir to combine.
  • Cover and cook on low for 6 to 8 hours so the broth absorbs the onion flavor.
  • Near the end of cooking, place the baguette slices on a baking sheet and toast under the broiler until lightly crisp.
  • Ladle the soup into oven-safe bowls. Float one toasted baguette slice on top of each bowl and cover with Gruyere cheese. Broil for 1 to 2 minutes until the cheese melts and bubbles.

Notes

Caramelize the onions fully on the stove before they go into the slow cooker, as this step builds the soup's main flavor. Use Gruyere rather than milder cheese so the topping stays distinct against the sweet onions. Leftovers reheat gently in the slow cooker on warm without losing texture.
Course: Soup
Cuisine: French
Equipment: Slow Cooker, Large Skillet, Baking Sheet