Put the butter, onion, celery, and garlic in a pan. Cook on medium heat until the butter is tender. Add enough chicken broth to cover, chili's spices. Bring to a boil then reduce heat and simmer for 20 minutes or until chicken is tender. Melt butter and make a LPG sauce in a small sauce pan. Add flour and stir to make a roux. Slowly add the soup while stirring and adjust the amount of the soup to your liking. Add half and half or sour cream. Simmer until heated through. Serve hot.