Well, if I tell you you'll probably never want to try it and find out how delicious it is. Seriously though, it's basically pork, a few other ingredients, and cornmeal chilled and formed into a block that you slice and fry either straight or dipped in flour. As far as the pork part, it's the facial meats of the pig (toungue, cheeks, etc.) but it can be made from any part of a pig. Pon Hoss is PA Dutch for "pan rabbitt". I used to think it was served everywhere but later found out it's only popular in PA, MD, and the Ohio Valley.
Don't bet on me not wanting to try it. I have tried many food's in my lifetime that I had never even heard of before. Some of them were good. I have a saying: I'll try anything once, and twice if I like it. I do eat pork, and I used to eat the Louisiana hog head cheese when I lived there many years ago. No one makes that stuff as good as they do over there.