In large bowl, cream together the butter and cream cheese with a hand mixer until smooth. Slowly add the powdered sugar until combined. Add egg, baking powder, vanilla, and salt. Mix to combine. Add flour in slowly until fully incorporated, scraping the sides as needed. Place in fridge for one hour to rest.
Preheat oven to 375°. In a small bowl, mix together the cinnamon and sugar. Set aside.
Roll dough into 1 inch sized balls, about 2 teaspoons worth of dough. Roll until coated in the
cinnamon sugar mixture. Place on a parchment lined cookie sheet about 2 inches apart.
Bake for 8-9 minutes,until just set. Do not overbake, it is hard to tell when these cookies are
ready, they will puff up but won't get golden brown. Let cool on baking sheet for 10 minutes. Transfer cookies to a wire rack and let cool completely.