Preheat air fryer to 360°F (or preheat oven to 350°F).
Mix all ingredients except for the chocolate chips/blueberries in a small bowl. *if you find your mixture is too dry, add milk- otherwise it should be fine to leave it out!
Form batter into a round ball and press into a cookie shape in the basket of the prepared air fryer (spray lightly with cooking spray) or on a prepared cookie sheet.
Add chocolate chips or blueberries on top and gently press them into the top of the cookie.
Air fry for about 8-10 minutes (or bake in the oven for 15 minutes)
