Heat the butter in a large pot over medium heat.
Add the onion, celery, and potatoes and sauté for about 5 minutes.
Add the clams and chicken broth and bring to a boil.
Reduce the heat to low and simmer for about 15 minutes or until the potatoes are cooked.
Add the cream, thyme, bay leaf, and salt and pepper to taste.
Simmer for an additional 5 minutes.
Serve the chowder hot and enjoy.