Same as regular schnitzel.
Dip chicken cutlets in flour, then beaten eggs, then follow with crushed pretzel crumbs (instead of corn flake crumbs or panko or whatever you normally use). Fry in hot oil, or spray baking pan with oil spray (Pam) then arrange cutlets, spray again, bake in oven.
You can add soy sauce (just a little) or ketchup or barbecue sauce to beaten eggs. Don’t add salt or other salty ingredients (onion soup mix and the like) to pretzel crumbs as they’re salty enough, but you can add some spices like garlic powder, onion powder, hot pepper flakes or whatever your family likes. I think most people just enjoy the salty pretzel-y flavor and don’t bother with much else.