Prepare Coating: In a shallow bowl, thoroughly combine sugar and cinnamon.

Shape Donuts: Using a 1-inch round cutter or bottle cap, cut center holes from each biscuit to form donut shapes.

Air Fry: Lightly coat air fryer basket with olive oil spray. Working in batches of 3-4 donuts, cook at 350°F / 176°C for 5-6 minutes until golden brown, flipping halfway through.

Coat & Serve: While still warm, brush each donut with melted butter, then thoroughly coat in cinnamon-sugar mixture. Best enjoyed immediately.