In a large pot over medium heat, melt the butter. Add onion and celery
cook until softened.
Whisk in flour into mixture creating roux while continuously stirring for about two minutes (until golden brown).
Slowly pour chicken stock or broth to prevent lumps forming, then bring the soup up to a simmer. Allow it to cook until thickened.
Stir in heavy cream and add chopped clams with their reserved juice into pot
stir thoroughly ensuring even distribution of ingredients throughout mixture.