In a large bowl mix together cake mix, cool whip and egg using a mixer. The texture can be thick and slightly sticky so using a mixer makes it much easier to handle.
Spray a baking sheet with cooking spray or line with parchment paper.
Using a cookie scoop, scoop one ball of dough into the sweetener or powdered sugar. Roll around and form a ball. Place onto cookie sheet. Repeat until you have 24 cookies.
Bake in the oven 10-14 minutes. The edges will be slightly brown. Edges and bottom will be slightly crisp and the inside will be super soft.