Combine flour,salt,and pepper on paper or plastic bag. Add a few necks at a time. Shake to coat.
Heat shortening or oil in stockpot on medium heat. Brown necks on all sides. Add onion, celery, garlic and bay leaf. Saute 3 minutes. Add water, bouillon cubes, celery seed and red pepper flakes. Cover. Cook on medium-low heat 2 hours or until meat is very tender. Add additional salt and pepper to taste, if needed.