Prepare the Mixture:

1. Combine Ingredients: In a large mixing bowl, combine the leftover mashed potatoes, shredded cheddar cheese, breadcrumbs, egg, garlic powder, onion powder, and fresh parsley (if using). Season with salt and pepper to taste.
2. Mix Together: Use a spoon or your hands to mix everything until well combined. The mixture should be firm but slightly sticky.

Shape the Puffs:

3. Form into Balls: Scoop about a tablespoon of the mashed potato mixture and roll it into a ball. Place the ball on a tray or plate. Repeat this process until all the mixture is used up.
4. Optional Coating: For an extra crispy coating, roll the potato balls in additional breadcrumbs or panko before frying.

Fry the Puffs:

5. Heat the Oil: Heat a few tablespoons of olive oil in a frying pan over medium heat. Once the oil is hot, carefully place the potato balls into the pan.
6. Cook Until Golden: Fry the puffs for about 2-3 minutes per side, or until golden brown and crispy on the outside. Use tongs or a slotted spoon to turn them gently.
7. Drain Excess Oil: Once the puffs are crispy and golden, transfer them to a paper towel-lined plate to drain excess oil.

Serve:

8. Serve Hot: Serve the Leftover Mashed Potato Cheese Puffs hot with your favorite dipping sauce or on their own as a tasty snack.