Slow cooker French onion soup

Ingredients

Start-to-finish: 5 hours (40 minutes active)

Serves 4-6 

6 tablespoons butter 

4 large yellow onions, sliced and separated into rings

1 tablespoon white sugar 

2 cloves garlic, minced 

½ cup cooking sherry or dry white wine 

7 cups beef broth (or use beef bouillon cubes)

1 teaspoon salt 

¼ teaspoon dried thyme 

1 bay leaf 

Sliced French bread 

½ cup shredded Gruyere or Swiss cheese

1/3 cup shredded Emmental or Swiss cheese 

¼ cup shredded Parmesan cheese 

2 tablespoons shredded mozzarella cheese 

Preparation

In a large, heavy pot, heat butter over medium-high heat. Add onions and cook until translucent, about 10 minutes. Sprinkle onions with sugar; reduce heat to medium. Cook, stirring frequently, until onions are soft and browned, at least 30 minutes. Stir in garlic and cook until fragrant, 1 minute. 

Stir sherry or wine into onion mixture, scraping bottom of pot to dissolve small bits of browned onion. Transfer onions into slow cooker and pour in beef broth. Season to taste with salt; stir in thyme and bay leaf. Cover, and cook 4-6 hours on high or 8-10 hours on low. 

About 10 minutes before serving, set oven rack about 8 inches from heat source and preheat the oven’s broiler. Arrange bread slices on baking sheet and broil until slices are toasted, 1-2 minutes per side. 

Combine cheeses in a bowl, tossing lightly. Fill oven-safe bowls ¾ full of onion soup and float a bread slice in each bowl. Top with about 2 tablespoons of cheese mixture per bowl. 

Place bowls onto a baking sheet and broil until cheese topping is lightly browned and bubbling, about 2 minutes.