Crockpot French Onion Soup

Ingredients:
3 large white onions, thinly sliced
6 Tbs butter
64 ounces beef stock
1 Tbs Worcestershire sauce
2 cloves garlic, minced
4 sprigs fresh thyme (or 1 tsp dried thyme)
1 Bay Leaf
8 slices French bread
1 cup Gruyere cheese shredded
1/2 cup Parmesan cheese shredded
Salt & Pepper, to taste

Directions:
1. In a large pan, add butter and cook til melted. Add the onions and cook over medium-low heat until golden and caramelized.
2. Once golden, add to the crockpot along with the remaining ingredients except for bread and cheese.
3. Cook on low for 6-8 hours. Or High for 4 hours
4. Remove and discard bay leaf and ladle the soup into bowls. Top with bread slices and some of each cheese. Broil 2-3 minutes or until cheese is melted and browned.