Separate the biscuits and place them on a cutting board. Use a small round cookie cutter or shot glass to remove centers. Lightly spray an air fryer basket with coconut oil spray and place a single layer of donuts in basket.
Air fry at 350 degrees for 3 minutes per side or until golden brown and flaky. Do this in batches. Do not discard the donut holes. Fry them separately, but for just 2 minutes per side.
Mix sugar and cinnamon together and place in a shallow dish. When the donuts and donut holes are done cooking, brush all sides with melted butter and roll in the sugar-cinnamon mixture until coated. Enjoy immediately!
Notes
An alternative to coating the donuts in a cinnamon sugar mixture is to dunk them in a simple glaze. Combine 1 cup powdered sugar with 2-3 tablespoons milk and mix until smooth.
To make a flavored glaze, consider replacing the milk with chocolate syrup for a chocolate glaze or maraschino cherry juice for a cherry icing!
Lightly coat the air fryer basket with coconut oil spray before cooking.
Have leftover donuts? Store in plastic wrap or an airtight container at room temperature for up to 3 days.
If you don't have a small enough glass to punch out the middle of the donut, use an apple corer or the top of an empty bottle (or a bottle cap!).