Description
A classic French Onion Soup made easy in the slow cooker, featuring deeply caramelized onions, rich beef broth, and a cheesy, broiled bread topping.
Ingredients
- 6 large yellow onions, thinly sliced
- 4 tbsp unsalted butter, melted
- 1 tsp granulated sugar
- 1/2 tsp salt
- 1/4 tsp black pepper
- 6 cups beef broth
- 1/2 cup dry white wine or dry sherry (optional, but recommended)
- 1 tbsp Worcestershire sauce
- 2 bay leaves
- French bread or baguette, sliced
- Gruyere cheese, shredded, or provolone slices
- Fresh thyme, for garnish (optional)
Instructions
- In a large bowl, toss the thinly sliced onions with melted butter, sugar, salt, and pepper until well coated.
- Transfer the seasoned onions to a 6-quart (or larger) slow cooker.
- Cover and cook on high for 3-4 hours or on low for 6-8 hours, or until the onions are deeply caramelized and very tender. Stir occasionally if cooking on high.
- Once onions are caramelized, stir in the beef broth, white wine/sherry (if using), Worcestershire sauce, and bay leaves.
- Cover and cook on high for an additional 1-2 hours, or on low for 2-4 hours, allowing the flavors to meld.
- Remove bay leaves before serving.
- To serve: Ladle soup into oven-safe bowls. Top each bowl with a slice or two of French bread and a generous amount of Gruyere cheese.
- Broil for 2-4 minutes, or until the cheese is melted and bubbly and golden brown. Watch carefully to prevent burning.
- Garnish with fresh thyme if desired and serve immediately.
Notes
- Ensure onions are sliced thinly and uniformly for even caramelization.
- Caramelization time may vary depending on your slow cooker.
- Watch the broiling step closely as cheese can burn quickly.