Preheat oven to 375°F. Line two baking sheets with parchment paper and set them aside.

In a large mixing bowl, cream together the butter, cream cheese, and sugar with a handheld mixer. Add the egg and vanilla. Mix well. Add the cake flour and baking powder. Mix well.

Refrigerate dough for at least an hour.

Scoop a walnut-size ball of cookie dough into the cinnamon sugar. Roll each ball until completely coated. Place cookie dough on the prepared baking sheet. Repeat with the remaining cookie dough.

Bake 9-11 minutes or until the underside edges just begin to turn golden.

Cool cookies on a baking sheet for 3-4 minutes before transferring to a cooling rack to cool completely.