For me, the best part of mashed potatoes is mashed potato cakes the next day. These are a fantastic base for poached eggs (think a potatoey eggs benedict) and make a great light lunch topped with salsa. Panko breadcrumbs are a perfect coating, but I've used matzo meal, grits or plain flour as a breading too. —Savorykitchen
Put breadcrumbs into a medium bowl. Using an ice cream scoop or quarter-cup measure or a big spoon, scoop mashed potatoes into crumbs, turn gently to coat. Set aside on a plate until ready to fry
Heat a cast-iron or non-stick skillet and pour in a thin layer of oil. When the oil is hot, add the cakes to the skillet and fry, flipping once, until nicely browned on both sides, about 3-4 minutes a side.