Mix potato, cheese and salt in a large bowl to combine.

Form into golf ball-sized balls and chill them on a plate in the fridge while you heat the oil for frying.

Pour 2” of oil into a heavy, high-sided pot and place over medium-high heat. When it reaches 375ºF on a thermometer, or a small piece of the kofta batter sizzles right away, slide (don’t drop) a few koftas into the hot oil using a slotted metal spoon. Fry in batches so you don’t overcrowd the oil.

Cook about 4 minutes, until golden brown, flipping once halfway through. Transfer to a plate lined with paper towels to drain. Repeat with remaining koftas.

If you are using actual leftover mashed potatoes, and have added cream and butter to them, you will need to add breadcrumbs until the balls hold together. Start with ¼ cup and add more as needed until a firm ball holds its shape. Fry a test one first before you do the rest.

Melt ¼ cup of butter in a small bowl. Roll koftas in the butter to coat then bake on parchment-lined baking sheet at 425ºF for 20 minutes, flipping every 5 minutes so that every side gets browned (they won’t be as round or as crispy).