In a large mixing bowl, mix the sour cream, egg, vanilla, oil, and sugar, then add in the flour, baking soda, salt, and ground nutmeg. Mix well.
Spray the donut molds with cooking spray, pour the batter about 2/3 the way in the mold, and then set them into the air fryer basket for 10-12 minutes at 320 degrees F, air fryer setting.
Remove from the air fryer basket and let cool slightly before glazing them.
To make the glaze, in a small mixing bowl, mix the powdered sugar, milk, and vanilla, mix well, and then dip your sour cream donuts into the glaze.
Place them on a drying rack to dry before serving
Plate, serve, and enjoy!