Preheat oven to 350 degrees F. Line a baking sheet with parchment paper, a silicone mat, or spray with nonstick cooking spray.
In a large mixing bowl add the cake mix, Cool Whip, egg, and lemon zest. Use a rubber spatula and mix together.
Add the powdered sugar to a small bowl.
Use a cookie scoop to get the cookie batter out then drop it into the powdered sugar. Use a fork to move it around the powdered sugar, then place it onto the baking sheet.
Bake for 9-13 minutes. Let cool for a minute then place cookies onto a cooling rack.