Increase heat to medium high and add celery and onion. Sauté for 5-7 minutes or until onions are soft. Add potatoes, garlic, red pepper (if using) and sauté 30 seconds. Sprinkle in flour and cook an additional 1 minute. Stir in chicken broth, reserved 2 ½ cups clam juice,
chicken bouillon, bay leaves and all seasonings. Bring to a boil then reduce to a simmer. Simmer, uncovered, for 15-20 minutes or until potatoes are very tender.