Prepare the Dough: In a large mixing bowl, combine 1 box of cake mix (15.25 oz), 2 cups of thawed Cool Whip, and 1 large egg. Mix them together until the mixture is smooth and evenly combined. The dough will be quite sticky, which is perfectly normal!
Chill the Dough: Cover the mixing bowl with plastic wrap and place the dough in the refrigerator for about 30 minutes. This chilling period will help firm up the dough, making it easier to roll into balls.
Roll and Coat: After chilling, preheat your oven to 350°F (175°C). Prepare a greased cookie sheet. Take a small amount of dough and roll it into balls, about 1 inch in diameter. Carefully coat each ball in ½ cup of powdered sugar to give them a sweet, snowy appearance. Make sure to space the cookie balls on the tray, as they will spread during baking.
Bake the Cookies: Place your cookie sheet in the preheated oven and bake for 12 minutes, or until the edges are golden brown. Keep an eye on them to avoid overbaking, as they can dry out quickly. Once baked, let them cool on the sheet for about 5 minutes before transferring them to a wire rack to cool completely.