Name: Slow Cooker French Onion Soup: 8 Hours of Comfort
Prep time: 15 min
Cook time: 8 h
Total time: 8 h 15 min
Cuisine: French
Ingredients: 6 large yellow onions, thinly sliced (about ¼ inch thick); 4 tablespoons unsalted butter; 2 tablespoons olive oil (extra virgin preferred); 6 cups beef broth (1.4 liters); ½ cup dry white wine (120 ml); 3 garlic cloves, minced; 3 sprigs fresh thyme (or 1 teaspoon dried thyme); 2 bay leaves; 1 tablespoon Worcestershire sauce; Salt and freshly ground black pepper to taste; 8 slices baguette, about ½ inch thick (day-old or lightly toasted); 2 cups shredded Gruyère cheese (200g)

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Slow Cooker French Onion soup is a delightful, hands-off recipe that transforms simple ingredients into a rich, savory comfort dish. This easy French Onion Soup Recipe features tender caramelized onions simmered in a flavorful broth, topped with gooey, melted Gruyère cheese. Perfect for cozy nights or gatherings, this recipe is designed for those who appreciate the deep flavors of classic French cuisine without much fuss.

Why You’ll Love This Slow Cooker French Onion

This Slow Cooker French Onion soup is not only delicious but also offers many benefits. First, it’s incredibly easy to make with minimal prep time. You simply throw the ingredients into the slow cooker and let it do the work for you! The slow cooking process enhances the flavors, producing a rich and hearty bowl of soup that’s perfect for chilly days. Additionally, this comforting soup is vegetarian-friendly, making it suitable for various diets. You can also serve it as a Slow Cooker Onion Soup for parties, ensuring everyone enjoys this warm dish. Lastly, it’s a fantastic recipe for meal prep, allowing you to enjoy leftovers throughout the week.

Ingredients for Slow Cooker French Onion

Gather these items:

6 large yellow onions, thinly sliced (about ¼ inch thick)
4 tablespoons unsalted butter
2 tablespoons olive oil (extra virgin preferred)
6 cups beef broth (1.4 liters)
½ cup dry white wine (120 ml)
3 garlic cloves, minced
3 sprigs fresh thyme (or 1 teaspoon dried thyme)
2 bay leaves
1 tablespoon Worcestershire sauce
Salt and freshly ground black pepper to taste
8 slices baguette, about ½ inch thick (day-old or lightly toasted)
2 cups shredded Gruyère cheese (200g)

How to Make Slow Cooker French Onion Step-by-Step

Step 1: Peel and thinly slice 6 large yellow onions about ¼ inch thick.
Step 2: Optional: Heat 2 tablespoons olive oil and 4 tablespoons butter in a large skillet over medium heat. Add onions and cook, stirring occasionally, until softened and golden, about 10-15 minutes.
Step 3: Transfer onions to slow cooker. Add minced garlic, ½ cup dry white wine, 6 cups beef broth, 3 sprigs fresh thyme, 2 bay leaves, and 1 tablespoon Worcestershire sauce. Stir to combine.
Step 4: Cook on low for 8 hours, allowing onions to caramelize and flavors to develop. Avoid lifting the lid frequently.
Step 5: After 8 hours, remove thyme sprigs and bay leaves. Taste and season with salt and pepper as needed. Preheat oven broiler and toast baguette slices on a baking sheet until golden, about 2-3 minutes per side.
Step 6: Ladle soup into oven-safe bowls. Place toasted baguette slices on top, then pile shredded Gruyère cheese generously over the bread.
Step 7: Place bowls on a baking sheet and broil until cheese is bubbly and golden brown, about 3-5 minutes. Watch closely to prevent burning.
Step 8: Carefully remove from oven and serve immediately.

Slow Cooker French Onion Soup: 8 Hours of Comfort - Slow Cooker French Onion - main visual representation

Pro Tips for the Best Slow Cooker French Onion

Keep these in mind:

Make sure to slice the onions evenly for consistent cooking.
Consider adding a splash of balsamic vinegar for an extra depth of flavor.
Use high-quality beef broth for the best taste.
Broiling the cheese is essential for that perfect gooey topping.

Best Ways to Serve Slow Cooker French Onion

Serve your Slow Cooker French Onion soup hot, garnished with fresh thyme or parsley for a pop of color. This dish pairs wonderfully with a crisp green salad or as an appetizer before a hearty meal. For a twist, consider using this soup as a Slow Cooker French Onion Dip for parties, served with crunchy vegetables or chips.

How to Store and Reheat Slow Cooker French Onion

To store any leftovers, let the soup cool completely, then transfer it to an airtight container. It can be kept in the fridge for up to 3 days. When ready to reheat, simply warm it on the stovetop or in the microwave until heated through. Avoid reheating it too quickly to prevent the cheese from burning.

Frequently Asked Questions About Slow Cooker French Onion

What’s the secret to perfect Slow Cooker French Onion?

The secret lies in the slow cooking process. Taking the time to let the onions caramelize enhances their sweetness and depth, creating a rich flavor that’s hard to beat.

Can I make Slow Cooker French Onion ahead of time?

Absolutely! You can prepare the soup a day in advance. Just store it in the fridge and reheat it before serving. This makes it an ideal option for gatherings.

How do I avoid common mistakes with Slow Cooker French Onion?

To avoid overcooked or burnt onions, be sure not to lift the lid frequently while it cooks. This allows steam to escape and can affect the cooking process.

Variations of Slow Cooker French Onion You Can Try

There are several delicious variations you can experiment with. Consider adding mushrooms for an earthy flavor, or swap out the Gruyère cheese for a melty Swiss or a vegan alternative. You can also make it a Caramelized Onion Slow Cooker dish by focusing solely on the onions, creating a fantastic base for other recipes.

For more information on the benefits of slow cooking, check out this Healthline article.

If you’re interested in more delicious soup recipes, visit our Cheesy Chicken Noodle Soup page.

For a delightful dessert to pair with your soup, try our Mini Cranberry Cheesecakes.

Lastly, for a hearty meal, consider making our Slow Cooker Beef Ramen.