In a medium bowl, mix together the mashed potatoes, egg, flour, salt, pepper, garlic, and chives, if using.
Preheat a large skillet with 2-3 Tbsp. of canola or enough to give an even layer in the pan.
Form the potato mixture into patties and fry them for a couple of minutes until they are golden brown. Turn over and fry them on the other side. Serve hot with a sprinkling of chives.