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Slow Cooker French Onion Soup

A warm, comforting bowl of Slow Cooker French Onion Soup with caramelized onions, rich beef broth, and melted Gruyère cheese, perfect for cozy gatherings.
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Prep Time 10 minutes
Cook Time 8 hours
Total Time 8 hours 10 minutes
Servings: 6 servings
Course: Main Course, Soup
Cuisine: French
Calories: 322
Ingredients Method Notes

Ingredients
  

Main Ingredients
  • 4 large onions, thinly sliced
  • 4 cups beef broth (Halal-approved)
  • 2 tablespoons butter
  • 1 tablespoon olive oil
  • 1 teaspoon fresh thyme
  • Salt and pepper to taste
  • Baguette slices (toasted)
  • Shredded Gruyère cheese

Method
 

Preparation
  1. Start by peeling and thinly slicing your onions. The thinner they are, the faster they will caramelize, giving you that sweet, rich flavor we crave.
  2. In a large skillet over medium heat, melt the butter and olive oil. Add the sliced onions and sauté for about 15 minutes until they become soft and golden brown. Stir occasionally for even cooking.
  3. Once the onions are caramelized, transfer them to a slow cooker.
  4. Pour the beef broth into the slow cooker along with fresh thyme and season with salt and pepper. Give it a gentle stir to combine.
  5. Cover and cook on low for 6-8 hours or high for 3-4 hours. This slow cooking time helps to meld all those wonderful flavors together!
  6. About 15 minutes before serving, toast your baguette slices until crispy and golden.
  7. Ladle the soup into bowls, place a toasted baguette slice on top, and sprinkle generously with shredded Gruyère cheese. For a final touch, you can broil it for a couple of minutes until the cheese is bubbly!

Notes

For substitutions, feel free to switch the beef broth with vegetable broth for a vegetarian version. If you're short on time, sautéing the onions in the slow cooker can yield similar flavor results. Avoid rushing the onion caramelization stage—it’s essential for that deep flavor! If you have leftovers, store them in an airtight container in the refrigerator for up to 5 days or freeze for up to 3 months.