French Onion Soup

Name: French Onion Soup
Prep time: 10 min
Cook time: 1 h 10 min
Total time: 1 h 20 min
Cuisine: French
Ingredients: 4 pounds yellow onions (halved and thinly sliced); 3 tablespoons butter; 2 cloves garlic (minced); 2 sprigs fresh thyme; 1 bay leaf; Salt and pepper to taste; 3 tablespoons all-purpose flour; 1/4 cup white wine or water; 6 cups beef stock; French bread (sliced); 2 tablespoons olive oil; Gruyere cheese (sliced or grated)