Crockpot French Onion Soup

This easy Crockpot French Onion Soup is loaded with sweet caramelized onions simmered in a rich, savory beef broth and topped with toasted baguette slices and plenty of melted Gruyere cheese. It’s a cozy slow cooker comfort food that’s perfect for a cold weather dinner with the family.

this recipe!

Try my crockpot chicken noodle soup and crockpot lasagna soup next!

Why You’ll Love This Recipe

• Rich, classic flavor: Caramelized onions, beef broth, red wine and fresh thyme create that delicious French onion soup flavor.
• Made in the slow cooker: After caramelizing the onions, the Crockpot does the rest of the work while all those savory flavors develop.
• Ultimate comfort food: Toasted baguette and bubbly melted Gruyere make this a warm and cozy dinner for chilly fall and winter nights.

Ingredients You’ll Need

• 6 tablespoons butter
• 3 lbs sweet onions, halved and thinly sliced
• 3-4 cloves garlic, minced
• ½ dry red wine
• 8 cups beef broth
• 1 tablespoon worcestershire sauce
• 1 tablespoon balsamic vinegar
• Salt and pepper, to taste
• 3 sprigs fresh thyme
• 2 bay leaves
• French baguette, sliced 1-inch thick
• 1 ½ cups shredded gruyere cheese
• ½ cup shredded parmesan cheese
• Fresh thyme, for topping

Step By Step Instructions

STEP ONE – Melt the butter in a large skillet or pot over medium heat. Add the sliced onions and cook for 20 to 30 minutes, stirring often, until they are deeply golden and caramelized. Reduce the heat if the onions begin to brown too quickly.

STEP TWO – Add the minced garlic and cook for another 2 to 3 minutes, stirring frequently, until fragrant.

STEP THREE – Pour in the red wine and scrape up any browned bits from the bottom of the skillet. Cook for a few minutes, until the wine has reduced slightly.

STEP FOUR – Transfer the caramelized onion mixture to a 6-quart Crockpot. Add the beef broth, Worcestershire sauce and balsamic vinegar. Season with salt and pepper, then add the fresh thyme sprigs and bay leaves.

STEP FIVE – Cover and cook on LOW for 8 hours or HIGH for 4 hours.

STEP SIX – During the last 30 minutes of cooking, preheat the oven broiler. Arrange the baguette slices on a baking sheet and broil for 2 to 3 minutes per side, until toasted and golden brown. Set aside.

STEP SEVEN – When the soup is finished cooking, remove and discard the bay leaves and thyme sprigs. Taste and adjust the salt and pepper as needed.

STEP EIGHT – Ladle the French onion soup into oven-safe bowls. Top each bowl with 2 to 3 toasted baguette slices, then sprinkle generously with the Gruyere and Parmesan cheese.

STEP NINE – Place the bowls on a baking sheet and broil for 3 to 4 minutes, until the cheese is melted, bubbly and lightly browned on top.

STEP TEN – Garnish with fresh thyme and serve immediately.