Fill a large tub with cold water. Drop in chitlins and soak undisturbed for 30 minutes or longer. Drain off water. With sharp knife, pull off fat under running water and throw away. Rinse the meat again under cold running water and let soak again for 1 hour, changing the water several times. Rinse the meat again under cold running water and place in a large pot. (CHITLINS MUST BE THOROUGHLY CLEANED). Cover with water; add onion, vinegar, crushed red pepper, salt and pepper and white potato. Bring to boil; reduce heat. Cover and simmer 3 hours or until chitlins are fork tender. Cut into small pieces. Serves about 8 people.