Slow Cooker French Onion Soup
- 3 pounds sliced white onions
- 8 tablespoons unsalted butter
- 1 teaspoon salt
- 8 cups beef broth
- 1 tablespoon Worcestershire sauce
- 1/4 cup white wine, (or white cooking wine)
- 1 tablespoon red wine vinegar
- 4 springs thyme, plus additional thyme for topping
- Loaf of Italian bread, cut into ¾-inch slices, for topping
- 2 cups shredded Gruyère cheese
Place onions, butter and salt in large slow cooker. Cook on low for 8-10 hours. This works best if you do it overnight.
- In the morning add beef broth, Worcestershire, wine, red wine vinegar and thyme. Season with salt and pepper to taste. Cover and cook on low for another 6-8 hours.
Heat oven to 350 F. Place ovenproof bowls onto baking sheet. Ladle soup into bowls. Top each bowl with 1-2 slices of bread and about ⅓ cup of shredded cheese.
Bake for 20 minutes.
Turn on broiler and broil until golden brown, keeping a very close eye on it.
Garnish with additional thyme leaves and enjoy!