In a large mixing bowl, combine cake mix, vanilla, eggs and thawed whipped topping. You can mix with an electric mixer for about 1-2 minutes, stopping every now and again to scrap down the sides of the bowl. Or get a little arm work out in and mix by hand. 

If the mixture isn't combining well (because the cake mix is so dry) add a teaspoon of water. Once everything is well blended. Cover with plastic wrap and cool in the refrigerator for at least 30 minutes. 

After the cookie dough has chilled, pre-heat the oven to 350-degrees. In a small bowl add the powdered sugar and then drop teaspoon fulls into the sugar and roll in the sugar until coated and rounded. 

Place cookies on an ungreased cookie sheet about an inch and 1/2 apart (I use wax paper to keep things from sticking) and bake for about 10 -12 minutes. Then remove and let the cookies cool for 2 minutes before putting them on a wire rack to cool completely.