Mix together cream cheese, butter, egg, vanilla, in a mixing bowl.
Add in the cake mix. Refrigerate for 30 minutes for a dough that's easier to work with.
Pour powdered sugar in to a small bowl for rolling.
Roll about a teaspoon of dough into balls, and roll into powdered sugar, placing them on to a greased cookie sheet or a silicone mat
Bake at 350 for 12 minutes. Allow cookies to cool.
Top with whipped cream and strawberry slice, right before serving.
Tip: If you're a fan of using the canned whipped cream, know that it will quickly evaporate. So if you're making a bunch of cookies, wait until the last minute before serving, to top with the cream.BUT, if you're using homemade whipped cream, you're probably safer to do it a bit in advance. (It just may make your cookie a little soggy if it sits too long.Think, "Strawberry Shortcake," when making these. Just like that dessert, you'd wait until right before serving to top it with the goods.)