Crockpot French Onion Soup Recipe

Introduction

French Onion Soup is a comforting classic with deeply caramelized onions and rich beef broth, perfect for chilly days. This slow-cooked Crockpot version makes the process simple and hands-off, delivering rich flavor without constant attention.

Ingredients

• 4 large onions, thinly sliced
• 6 cups beef broth
• 2 tbsp butter
• 1 tsp sugar
• 1 tsp dried thyme
• Salt and pepper, to taste
• French bread, sliced and toasted
• 2 cups Gruyère cheese, shredded

Instructions

1. Step 1: Add the sliced onions, butter, and sugar to the Crockpot. Cook on high for 4 hours, stirring occasionally, until the onions are deeply caramelized.
2. Step 2: Stir in the beef broth, dried thyme, salt, and pepper. Cook on low for 4 to 5 hours to let the flavors meld.
3. Step 3: When ready to serve, ladle the soup into ovenproof bowls. Top each bowl with toasted French bread slices and sprinkle shredded Gruyère cheese over the bread.
4. Step 4: Place the bowls under the broiler for 2 to 3 minutes, until the cheese is melted, bubbly, and golden brown. Serve immediately.

Tips & Variations

• Use low-sodium beef broth to control the saltiness and enhance the soup’s natural flavors.
• For extra depth, add a splash of dry white wine or sherry before cooking on low.
• Gruyère can be substituted with Swiss or mozzarella cheese for a different but still melty topping.
• Toast the bread slices with a little garlic butter for added richness.

Storage

Store any leftover soup in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stovetop over low heat. For the best texture, add fresh toasted bread and cheese before serving again.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this soup without a Crockpot?

Yes, you can caramelize onions in a large pot on the stove over low heat, which may take about 45 minutes. Then add broth and simmer for 30–45 minutes before serving.

What can I use if I don’t have Gruyère cheese?

Swiss cheese, mozzarella, or even a mild fontina are good alternatives that melt well and complement the soup’s flavor.

Crockpot French Onion Soup Recipe

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★★★★★

4.5 from 87 reviews

This Crockpot French Onion Soup recipe offers a rich and comforting classic French dish made easy with slow cooking. Sweet caramelized onions simmered in beef broth with thyme create a deep flavorful base, topped with toasted French bread and melted Gruyère cheese for an indulgent finish.

• Author: Clara
• Prep Time: 15 minutes
• Cook Time: 8-9 hours
• Total Time: 8 hours 15 minutes
• Yield: 6 servings 1x
• Category: Soup
• Method: Slow Cooking
• Cuisine: French

Ingredients

Scale 1x2x3x

Soup Ingredients

• 4 large onions, thinly sliced
• 6 cups beef broth
• 2 tbsp butter
• 1 tsp sugar
• 1 tsp dried thyme
• Salt and pepper, to taste

Toppings

• French bread, sliced and toasted
• 2 cups Gruyère cheese, shredded

Instructions

1. Caramelize the Onions: Add the thinly sliced onions, butter, and sugar to the Crockpot. Cook on high for 4 hours, stirring occasionally until the onions become deeply caramelized and golden brown, developing rich sweetness and flavor.
2. Add Broth and Seasonings: Pour in the beef broth, then add dried thyme, salt, and pepper. Reduce heat to low and cook for an additional 4-5 hours to allow the flavors to meld together for a hearty soup base.
3. Prepare Bowls and Toast Bread: While the soup is finishing, slice French bread and toast it until crisp, ready for topping the soup before serving.
4. Assemble and Broil: Ladle the hot soup into ovenproof bowls, place a slice or two of toasted French bread on top, then generously sprinkle shredded Gruyère cheese over the bread. Place the bowls under a preheated broiler for 2-3 minutes, until the cheese is melted, bubbly, and slightly browned.

Notes

• Stir the onions occasionally during the caramelization step to prevent burning and ensure even cooking.
• For a vegetarian version, substitute beef broth with vegetable broth and use a vegetarian cheese alternative.
• Use oven mitts when broiling the cheese-topped bowls, as they will be very hot.
• Leftover soup can be refrigerated for up to 3 days and reheated gently on the stovetop.

Keywords: Crockpot French Onion Soup, slow cooker soup, caramelized onion soup, classic French soup, Gruyère cheese soup