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Slowcooker French Onion Soup

Slowcooker French Onion Soup Recipe

Slowcooker French Onion Soup is a variation of the classicFrench dish, made even easier by using a slow cooker. It typically consists ofcaramelized onions, beef broth, white wine, and a blend of herbs like thyme andbay leaves. The soup is topped with toasted baguette slices and melted cheese,creating a satisfying and flavorful meal that’s perfect for chilly days.
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Prep Time 15 minutes
Cook Time 6 hours
Course: Soup
Cuisine: French
Calories: 230
Ingredients Equipment Method Notes

Ingredients
  

  • 4 large yellow onions thinly sliced
  • 3 tablespoons butter unsalted
  • 4 cloves garlic minced
  • 4 cups beef broth or vegetable broth for a vegetarian version
  • 1 cup dry white wine optional, but highly recommended for a rich flavor
  • 1 teaspoon fresh thyme or ½ teaspoon dried thyme
  • 1 bay leaf
  • Salt and pepper to taste
  • 1 French baguette cut into slices
  • 2 cups shredded Gruyère cheese or Swiss cheese
  • 1 cup shredded mozzarella cheese optional, for extra melt

Equipment

  • Slow Cooker
  • Sharp knife
  • Cutting board
  • Wooden Spoon or Ladle
  • Measuring Cups & Spoons
  • Oven-safe Crockery or Bowls
  • Broiler or Oven

Method
 

  1. Sauté the Onions: Before adding the onions to the slow cooker, we’ll give them a quick sauté to enhance their flavor. In a large skillet, melt the butter over medium heat. Add the sliced onions and cook them for about 5-7 minutes until they soften slightly. Stir occasionally to prevent burning.
  2. Add the Garlic: Once your onions are soft, add the minced garlic to the skillet and cook for another minute until fragrant. This step helps infuse the soup with a deep, savory flavor.
  3. Transfer to Slow Cooker: Transfer the onions and garlic mixture to your slow cooker. Add in the beef broth, wine (if using), thyme, and bay leaf. Season with salt and pepper to taste. Give it all a good stir to combine.
  4. Slow Cook: Cover the slow cooker and set it on low. Let the soup cook for 6-8 hours, or until the onions are tender and the flavors have fully developed. If you’re in a rush, you can cook it on high for 3-4 hours, but slow and steady is the key to the best flavor.
  5. Prepare the Baguette and Cheese: About 30 minutes before the soup is ready, preheat your oven to broil. Slice the French baguette into rounds and toast them in the oven until crispy and golden. Once toasted, top each piece with a generous amount of shredded Gruyère cheese.
  6. Serve and Broil: Once the soup is ready, ladle it into oven-safe bowls, top with the cheesy baguette slices, and place the bowls under the broiler for 2-3 minutes until the cheese is bubbly and golden.

Notes

Tip for the best flavor: Don't skip the slow-cooking step. The key to great French Onion Soup is the slow caramelization of the onions, which builds layers of flavor. If you’re feeling fancy, you can even add a splash of brandy or balsamic vinegar for an extra kick!