In a mixing bowl, combine the all-purpose flour, granulated sugar, baking powder, salt, and ground cinnamon. Mix well.

In another bowl, whisk together the milk, melted butter, egg, and vanilla extract until well combined.

Gradually add the wet ingredients into the dry ingredients and mix until a dough forms. Do not overmix.

Lightly flour your work surface and turn the dough out onto it. Roll the dough out to about ½ inch thickness.

Use a cookie cutter or round mold to cut out donut shapes. Gather any scraps and re-roll to cut out additional donuts.

Preheat your air fryer to 350°F (175°C) for about 5 minutes.

Lightly spray the air fryer basket with cooking spray or brush it with oil.

Place the donut biscuits in the air fryer basket in a single layer, making sure they are not touching.

Air fry the donuts for around 8-10 minutes or until they are golden brown and cooked through. Adjust cooking time if necessary.

Carefully remove the donuts from the air fryer and allow them to cool slightly before topping them with powdered sugar or glaze if desired.

For a simple glaze, mix one cup of powdered sugar with 2-3 tablespoons of milk and a splash of vanilla extract.