Peel and wash: Peel the potatoes, cut them into medium pieces, and wash well.
Boil the potatoes: Bring a pan of water to a boil. Add the potato pieces and cook for 10 to 15 minutes until fork-soft. Drain all the water and let them cool for 4 to 5 minutes.
Mash and mix: Add the cooled potatoes to a mixing bowl and mash until smooth. Add cornstarch, salt, and black pepper. Mix until the mixture is smooth and shapeable. If too soft, refrigerate for 15 to 20 minutes.
Shape the balls: Roll the mixture into round balls of your preferred size.
Preheat the air fryer: Preheat to 190°C (375°F) for 2 to 3 minutes.
Air fry: Lightly spray the basket. Arrange the balls with space between them and spray the tops. Air fry at 190°C (375°F) for 12 to 15 minutes, flipping carefully at the 6 to 7 minute mark, until golden and crispy.
Serve: Remove from the air fryer and serve hot with tomato ketchup, mayonnaise, or your favourite dip.