Name: Crockpot French Onion Soup
Prep time: 20 min
Cook time: PT-488128H41M18S
Total time: PT-488128H41M18S
Cuisine: French
Ingredients: 6 large yellow onions, thinly sliced; 4 tablespoons butter; 3 cloves garlic, minced; 1/2 cup dry white wine or cooking sherry; 8 cups low-sodium beef broth; 1 tablespoon Worcestershire sauce; 1 bay leaf; 1 teaspoon fresh thyme or 1/2 teaspoon dried thyme; Salt and pepper to taste; 1 baguette or French bread, sliced and toasted; 2 cups shredded Gruyère or Swiss cheese

Crockpot French Onion Soup is a warm, rich, and comforting dish that brings together the sweetness of caramelized onions, the depth of beef broth, and the irresistible melt of gooey cheese over toasted bread. Making it in a slow cooker allows all the flavors to develop slowly and naturally, resulting in a deeply savory soup that’s both elegant and hearty. Crockpot French Onion Soup

Why You’ll Love This Recipe

I love this recipe because it makes a traditionally time-consuming dish easy to prepare with the help of a crockpot. I just toss everything in, let it cook low and slow, and the result is a restaurant-quality soup right at home. The house fills with a mouthwatering aroma, and the flavors get even better as they simmer for hours. It’s perfect for cozy dinners or when I want to impress guests without standing over the stove for hours.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

Yellow onions, thinly sliced
Butter
Garlic, minced
Dry white wine or cooking sherry
Beef broth (low-sodium preferred)
Worcestershire sauce
Bay leaf
Fresh thyme or dried thyme
Salt and pepper to taste
Baguette or French bread, sliced and toasted
Gruyère cheese or Swiss cheese, shredded

Directions

I start by caramelizing the onions. In a skillet over medium heat, I melt butter and cook the sliced onions until they become soft, golden, and sweet. This step is key for building flavor.
Once the onions are caramelized, I add the minced garlic and sauté it for about 1 minute until fragrant.
I deglaze the pan with wine or sherry, scraping up any brown bits from the bottom.
I transfer the onions and garlic mixture to my crockpot. Then I add the beef broth, Worcestershire sauce, bay leaf, thyme, salt, and pepper.
I cover and cook on low for 6 to 8 hours, or on high for about 3 to 4 hours.
When the soup is ready, I toast slices of baguette until crisp.
I ladle the soup into oven-safe bowls, top each with a toasted bread slice, and generously sprinkle shredded cheese on top.
I place the bowls under a broiler for a few minutes until the cheese is bubbly and golden.

Servings and timing

This recipe makes about 6 servings. The prep time is around 20 minutes, and the total cooking time is approximately 6 to 8 hours on low or 3 to 4 hours on high in the crockpot.

Variations

Sometimes I like to switch up the cheese and use provolone or a mix of Gruyère and mozzarella for a different melt and flavor. If I want a vegetarian version, I replace the beef broth with mushroom or vegetable broth and skip the Worcestershire sauce (or use a vegetarian version). Adding a splash of balsamic vinegar can also deepen the flavor even more.

Storage/reheating

I store any leftovers in an airtight container in the refrigerator for up to 4 days. When I’m ready to reheat, I warm the soup gently on the stovetop or in the microwave. If I want to re-create the original serving style, I toast new bread slices and melt cheese over them under the broiler before adding to the reheated soup.

FAQs

How do I properly caramelize onions for this soup?

I cook them slowly over medium-low heat with butter, stirring occasionally until they turn a deep golden brown. It usually takes 30–40 minutes, but the flavor payoff is worth it.

Can I make this soup ahead of time?

Yes, I often prepare the soup a day in advance. The flavors develop even more overnight in the fridge.

What type of onions work best?

I find that yellow onions are ideal for their balance of sweetness and flavor. I sometimes mix in a sweet onion or two for extra richness.

Can I freeze Crockpot French Onion Soup?

Absolutely. I freeze the soup without the bread and cheese in airtight containers for up to 3 months. I just thaw and reheat it before serving with freshly toasted bread and cheese.

What kind of bread should I use?

I like using crusty baguette slices because they hold up well under the broiler and absorb the soup without falling apart.

Conclusion

Crockpot French Onion Soup is a classic comfort food that’s surprisingly easy to make. I love how the slow cooker brings out the depth of flavor with minimal effort. Whether I’m making it for a weeknight dinner or a cozy weekend meal, it always hits the spot. With rich broth, caramelized onions, melty cheese, and crusty bread, it’s a dish I keep coming back to again and again.