Snitz = dried or dehydrated apple slices. Harr Har...thought you were a little Dutch. LOL You are going to have to dig into an old Pennsylvania Dutch cookbook or one from an old plain church group. Finding out what the Nep is shall require some research.
From Pa. Dutch Hatfield, I suspected the spelling might be a challenge since we usually HEAR words rather than SEE the words. I looked online and found a recipe for "SCHNITZ UND KNEPP (Ham and Dried Apples with Dumplings) Schnitz und Knepp is an old Pennsylvania Dutch recipe meaning 'Apples and Buttons' with the dumplings being the buttons."