<human>:  I want to find a good recipe for French onion soup.
<bot>: One of the best recipes for French onion soup is to start by melting 4 tablespoons of butter in a large pot over medium heat. Once the butter is melted, add 5 large yellow onions sliced into thin strips and cook until softened, about 8-10 minutes. Add 8 cups of beef broth, 1 bay leaf, and 1 teaspoon of dried thyme to the pot. Bring the soup to a boil and simmer for 40 minutes. Finally, season with salt and pepper to taste. Serve the soup with toasted baguette slices and top with grated parmesan cheese. Enjoy!