Go Back
A bowl of crockpot French onion soup with melty cheese and croutons

Speedy Crockpot French Onion Soup

This Speedy Crockpot French Onion Soup recipe streamlines the classic dish, slow-cooking rich, savory broth and sweet caramelized onions to perfection. Topped with cheesy baguette, it's comfort in a bowl.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 2 hours 1 minute
Total Time 2 hours 16 minutes
Servings 4 bowls
Calories 350 kcal

Equipment

  • Large skillet or Dutch oven
  • Slow cooker
  • Oven broiler
  • Baking sheet
  • Oven-safe bowls

Ingredients
  

Main Ingredients

  • 4-5 medium-sized large yellow onions thinly sliced
  • 4 tablespoons unsalted butter
  • 2 cloves garlic minced
  • 6 cups high-quality low-sodium beef broth
  • 1/2 cup dry red wine Merlot or Cabernet Sauvignon, optional
  • 1 tablespoon Worcestershire sauce
  • 3-4 fresh thyme sprigs
  • 1 bay leaf
  • Salt to taste
  • Freshly ground black pepper to taste

For Serving

  • 1 baguette sliced into 1-inch thick rounds
  • 8 ounces Gruyere cheese grated

Instructions
 

Preparation

  • Melt butter in a large skillet over medium heat, then add thinly sliced onions and cook for 15-20 minutes until softened and golden.
  • Stir in minced garlic and cook for another minute until fragrant.
  • Pour in red wine (if using) and scrape up any browned bits; cook for 2-3 minutes until the liquid mostly evaporates.

Slow Cooking

  • Transfer caramelized onions and garlic to a slow cooker.
  • Add beef broth, Worcestershire sauce, thyme sprigs, bay leaf, salt, and pepper to the slow cooker.
  • Cover and cook on high for 1.5 to 2 hours until onions are tender and broth is deeply flavored.

Finishing Touches

  • Preheat oven broiler, arrange baguette slices on a baking sheet, and toast for 1-2 minutes per side until lightly golden.
  • Ladle hot soup into oven-safe bowls, place toasted baguette slices over each, and generously sprinkle with grated Gruyere cheese.
  • Broil the soup bowls for 2-4 minutes until the cheese is melted, bubbly, and golden brown, watching carefully to prevent burning.
  • Serve immediately and enjoy your comforting French Onion Soup.

Notes

For a richer flavor, consider using a good quality beef broth or making your own. The red wine is optional, but it adds a nice depth of flavor to the soup. Gruyere cheese is traditional, but Swiss cheese or a blend of melting cheeses can also be used. This soup is perfect for a cozy evening or as an appetizer for a dinner party.