Remove clams from shell and soak in milk overnight, or as long as possible.
Beat egg whites with pinch of salt and pepper using a fork for one minute.
Dredge clams in flour, then egg white, then panko. Set aside
Heat oil in a medium saucepan until a small amount of egg batter begins to fry on contact (medium-high heat).
Put hoagies in toaster or under oven broiler.
Fry battered clams for four to five minutes, turning once after three minutes or edges turn golden-brown. Don't overcook.
After removing clams from frying oil, chop them coarsely.
Serve on hoagie with lettuce, tomato, and generous amount of tartar.