We love using leftover pork tenderloin because it stays tender even when reheated! Next time you make pork tenderloin, consider making a double batch so you can use the rest for leftovers. Our favorite way to use it is in a stir fry, but you can also season it and use it to make tacos, make fried rice, or thinly slice it for sandwiches (it would be especially perfect in a Cuban sandwich).