In a mixing bowl, combine chilled leftover mashed potatoes with shredded cheese, one beaten egg, and breadcrumbs. Sprinkle in your choice of spices, like garlic powder, salt, and pepper. Stir until well blended.

With clean hands, take portions of the mixture and roll them into small balls, about golf ball size, or shape them into small patties. Place on a parchment-lined baking sheet with space between each.

Preheat your oven to 400°F (200°C). Ensure your puffs are evenly shaped and spaced, then give them a light spray of cooking oil.

Bake the puffs for 20-25 minutes, or until golden brown. Rotate halfway through for even baking.

Allow to cool for a few minutes, then serve warm with dipping sauces of your choice.