This Pacific hard-shell clam is considered one of the choicest of its genre. Unfortunately, it's also becoming one of the scarcest. Pismos are tender, sweet and large — usually with a minimum shell diameter of 5 inches. The adductor muscle (which hinges the two shells) is so tender that it can be served on the half shell. The body meat can be steamed, fried or used in chowder. See also clam.