gravy or mayonnaise....like I always do. I'm actually not a big ketchup person. As for the gravy, always on the side for dipping, the only time I have gravy put on the fries is if it's a poutine.
I am fine with crispy crinkle cut fries and a little salt. I rarely use ketchup on them. I actually rarely use ketchup on anything. I have lettuce, tomato, and mayo on a cheeseburger.