In a medium bowl, with an electric mixer, cream together the cream cheese and butter until thoroughly combined.
Beat in the egg and vanilla until incorporated.
Add cake mix, and mix until thoroughly incorporated.
Cover dough and refrigerate for one hour.
Preheat oven to 350°F and line a baking sheet with parchment paper.
Portion the dough into 1-inch cookie balls and roll the balls in the powdered sugar. Place cookie dough balls on prepared cookie sheet, at least 2 inches apart.
Bake in preheated oven for 9-12 minutes. Allow cookies to cool on the pan before removing them to a wire rack.
If desired, sprinkle cooled cookies with additional powdered sugar before serving.
Notes
Dough refrigeration is not required, but recommended because it makes the dough less sticky; therefore, it's easier to roll.Store Gooey Butter Cookies in an airtight container at room temperature for up to 3 days.Adapted from allrecipes.