In a spacious mixing bowl, combine your creamy mashed potatoes with the shredded cheddar cheese, grated Parmesan, and finely chopped green onions.
Add the garlic powder, onion powder, salt, and black pepper to the bowl. Mix everything thoroughly until all ingredients are well incorporated and the mixture is smooth.
With clean hands, take a generous tablespoon of the potato mixture and roll it into a tight ball. Repeat this step until you've shaped approximately 12-15 balls from the entire mixture.
To prepare for breading, create a breading station: place the beaten egg in one shallow bowl and the panko breadcrumbs in another.
Take each potato ball and dip it into the beaten egg, ensuring it is fully coated. Then roll it in the panko breadcrumbs until it's completely covered.
Preheat your air fryer to 375°F (190°C) for about 5 minutes to get it nice and hot.
Lightly spray the air fryer basket with cooking spray to prevent sticking.
Arrange the breaded potato balls in the air fryer basket in a single layer, making sure they don't touch. Give the tops a light spray of cooking spray to aid browning.
Air fry the potato balls for 12-15 minutes, or until they turn golden brown and crispy, flipping them halfway through the cooking time for even crispness.
Once cooked, carefully remove the potato balls from the air fryer and let them rest for a few minutes to cool before serving.
Notes
Serve warm with dipping sauces like ranch or marinara.