Preheat the air fryer. Set it to 350°F (175°C) for about 3 minutes. Lightly spray the basket with nonstick spray or brush with a tiny bit of oil.

Prep the biscuits. Open the biscuit can and separate the rounds. Use a small round cutter, bottle cap, or the end of a piping tip to punch a hole in the center of each biscuit. Save the holes for donut holes.

Arrange in the basket. Place 3–4 donuts in a single layer, leaving space for air to circulate. Don’t crowd them—work in batches if needed.

Air fry the donuts. Cook for 5–6 minutes, flipping halfway, until golden brown and puffed. Thicker biscuits may need an extra minute.

Cook the donut holes. Air fry the holes for 3–4 minutes, shaking the basket halfway. They brown faster, so keep an eye on them.

Brush with butter. While still warm, lightly brush each donut with melted butter. This helps toppings stick and adds flavor.

Add your coating. For cinnamon sugar, mix sugar and cinnamon in a shallow bowl and toss the warm donuts to coat. For glaze, whisk powdered sugar, milk, and vanilla until smooth, then dip or drizzle over slightly cooled donuts. Add sprinkles or toppings while the glaze is wet.

Serve warm. These are best enjoyed fresh, while the outside is lightly crisp and the inside is soft.