This Slow Cooker French Onion Soup is the ultimate comfort food for cold days. With its deep, rich flavors and melt-in-your-mouth caramelized onions, it’s a classic dish made even easier. The slow cooker does all the work, giving you time to relax or prepare other parts of your meal.
To start, you’ll slowly caramelize the onions, allowing their natural sweetness to develop. Then, with a few simple ingredients like beef broth, thyme, and garlic, the soup simmers to perfection. As a finishing touch, a slice of crusty bread topped with melted Gruyère cheese adds the perfect balance of texture and flavor.
Whether you're preparing dinner for the family or hosting a cozy gathering, this French Onion Soup is always a hit. Plus, it's perfect for leftovers—just heat it up, and it’s as good as fresh. Try it once, and you’ll want to make it again and again!
This Slow Cooker French Onion Soup is the ultimate comfort food for cold days. With its deep, rich flavors and melt-in-your-mouth caramelized onions, it’s a classic dish made even easier. The slow cooker does all the work, giving you time to relax or prepare other parts of your meal.
In a large skillet over medium heat, melt the butter. Add the thinly sliced onions and cook, stirring occasionally, until the onions are caramelized and golden brown, about 20-25 minutes. Add garlic in the last few minutes of cooking. (Optional: You can add 1 tablespoon of sugar to help caramelize the onions faster.)
Once the onions are caramelized, transfer them to the slow cooker. Add the beef broth, Worcestershire sauce (if using), thyme, and bay leaves. Stir to combine.
Cover and cook on low for 6-8 hours, or on high for 3-4 hours, until the soup is rich and flavorful. Taste and adjust the seasoning with salt and pepper as needed.
While the soup is cooking, preheat the oven to 350°F (175°C). Slice the baguette into 1-inch pieces and place them on a baking sheet. Toast them in the oven for 10-15 minutes, or until golden and crisp.
Once the baguette slices are toasted, remove them from the oven. Top each slice with a generous amount of grated Gruyère cheese. Return them to the oven and broil for 2-3 minutes, until the cheese is melted and bubbly.
Ladle the soup into bowls and place a cheese-topped baguette slice on top of each bowl. For extra cheesiness, add another sprinkle of Gruyère directly into the soup. Serve hot and enjoy!
Servings 6
* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.