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–+ servings

Slow Cooker French Onion Soup

This slow cooker french onion soup is an easy, hands-free take on a classic! With rich, beefy broth and plenty of caramelized onions topped with melty Gruyere cheese, made in the slow cooker.
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Prep Time 10 minutes
Cook Time 12 hours
Total Time 12 hours 10 minutes
Course Breakfast
Cuisine American
Servings 6
Calories 120 kcal

Ingredients
  

Main Ingredients

  • 6 large sweet onions thinly sliced
  • 4 tablespoons unsalted butter melted
  • 0.25 teaspoon sugar
  • 0.5 teaspoon salt
  • 0.5 teaspoon fresh ground black pepper
  • 4 sprigs fresh thyme
  • 1 bay leaf
  • 6 cups low sodium beef broth
  • 0.5 cup dry white wine

For Serving (Optional)

  • 6 slices French bread toasted
  • 1.5 cups shredded Gruyere cheese

Instructions
 

Preparation Steps

  • Place the sliced onions in a 6-quart slow cooker. Stir in the melted butter, sugar, salt, and pepper. Top with thyme sprigs and the bay leaf. Place the lid on the pot and cook on LOW for 8 hours, or until the onions are deeply browned and caramelized. Stir halfway through the cooking time.
  • Once the onions are caramelized, stir in the beef broth and dry white wine. Taste the broth and season with additional salt and pepper as needed.
  • Cover the slow cooker and cook on LOW for another 4 hours, or on HIGH for 2 hours, until the soup is heated through.
  • Remove the lid and discard the thyme sprigs and bay leaf. Ladle the hot soup into oven-safe bowls. Place the bowls on a baking sheet.
  • Top each bowl of soup with a slice of toasted French bread and a generous amount of shredded Gruyere cheese.
  • Turn your oven's broiler to high. Place the baking sheet with the soup bowls under the broiler and broil for 2-3 minutes, or until the cheese is melted and bubbly and lightly browned.
  • Carefully remove the baking sheet from the oven and serve the French onion soup immediately.

Notes

For an even richer flavor, you can use a combination of beef and chicken broth. Ensure your oven-safe bowls are suitable for broiling.

Nutrition

Serving: 200gCalories: 120kcalCarbohydrates: 120gProtein: 120gFat: 120gSaturated Fat: 120gPolyunsaturated Fat: 120gMonounsaturated Fat: 120gTrans Fat: 120gCholesterol: 120mgSodium: 120mgPotassium: 120mgFiber: 120gSugar: 120gVitamin A: 120IUVitamin C: 120mgCalcium: 120mgIron: 120mg
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