Place the mashed potatoes in a medium mixing bowl.
Add the cornstarch or arrowroot powder to the mashed potatoes.
Mix thoroughly until a firm dough forms.
The dough should resemble a thick gnocchi-style dough and should hold its shape easily.
If the mixture is too soft or sticky, add additional cornstarch or arrowroot powder, 1 tablespoon at a time, until the desired texture is reached.
Using clean hands, portion the dough into small balls, slightly smaller than a golf ball.
Roll each portion until smooth and evenly shaped.
Transfer the potato balls to the air fryer basket in a single layer.
Leave space between each potato pop to allow proper air circulation.
Spray the potato pops generously with cooking spray.
Air fry at 450°F for 15 to 20 minutes, or until the exterior is golden brown and lightly crisp.
Check near the end of cooking, as air fryer temperatures may vary.
Remove the potato pops from the air fryer.
Serve immediately while hot and crisp.