Prepare the Mixture

1. Mix Ingredients: In a mixing bowl, combine leftover mashed potatoes, shredded cheese, green onions, garlic powder, salt, and pepper. Mix until well combined.
2. Form Balls: Scoop a spoonful of the potato mixture and roll it into a ball, about the size of a golf ball. Repeat with the remaining mixture.

Coat the Balls

1. Set Up Coating Station: Place the beaten eggs in one bowl and the breadcrumbs in another.
2. Dip and Coat: Dip each potato ball into the beaten eggs, then roll it in the breadcrumbs until fully coated.

Fry the Potato Balls

1. Heat the Oil: In a large skillet, heat about 1 inch of vegetable oil over medium heat until hot (about 350°F/175°C).
2. Fry the Balls: Carefully add the potato balls to the hot oil in batches, making sure not to overcrowd the pan. Fry for 3-4 minutes on each side, or until golden brown and crispy.
3. Drain: Use a slotted spoon to remove the balls from the oil and place them on a paper towel-lined plate to drain excess oil.