To make this amazing Slow Cooker French Onion Soup You’ll need the following ingredients:
French Onion Soup
30 minutes active; 4 hours inactive to prepare serves 8
4 pounds yellow onions, peeled and chopped
10 cups beef broth
1 baguette, sliced diagonally and toasted
1 bay leaf
1 1/2 cups Gruyere or swiss cheese, grated or sliced
1/2 cup (1 stick) unsalted butter, melted
1/4 cup all-purpose flour
2 tablespoons extra-virgin olive oil
2 tablespoons balsamic vinegar
1 tablespoon Worcestershire sauce
Kosher salt and freshly ground pepper, to taste
Minced chives, for garnish
Place chopped onions, butter, and olive oil in a large skillet or pot, and cook over medium heat for 10-15 minutes, or until onions start to caramelize.
In a small bowl, whisk flour into balsamic vinegar and Worcestershire sauce and mix until smooth.
Transfer onions to slow cooker. Pour in beef broth, bay leaf, salt, pepper, and flour mixture, and stir well to combine.
Cover and cook on low for 6-8 hours, or on high for 3-4 hours.
Ladle soup into oven proof bowls, top each with 1 slice of bread and cheese, and broil, about 5 minutes or until cheese is melted and bubbly.
Garnish with chives, serve hot and enjoy!