Can I slice the potatoes by hand?
Yes, no problem at all! It's very quick and easy to slice them with a food processor attachment or mandolin. But if you don't have either of these, slicing by hand is fine too. Just slice 3 to 4 mm thick slices as evenly as you can, but don't worry about getting them perfect. Just slice quickly and confidently with a small sharp knife. You're only slicing 5 or 6 potatoes so it won't take too long.