In a stand mixer fitted with the paddle attachment, mix the butter, apple butter, and sugar together until incorporated, but not light and fluffy. (Do not cream together for very long.)
Add the egg and vanilla. Mix until combined.
In a separate bowl, combine the flour, cream of tartar, baking soda, salt, and cinnamon. Add dry ingredients to butter mixture and mix until combined.
REFRIGERATE dough for 1-2 hours.
Preheat oven to 350 degrees Fahrenheit. Line baking sheets with silicone or parchment paper.
Mix cinnamon and sugar together in a bowl for coating. Scoop dough into balls (with a #30 scoop) and roll in cinnamon-sugar until fully coated. Place the coated dough balls on a prepared baking sheet several inches apart.
Bake at 350˚F for 15 minutes, until the cookies have spread, the edges and bottom have browned, but the dough peeking through the cracks looks just slightly wet still. Remove from oven and leave cookies on the tray for 5 minutes before transferring to a wire rack to cool completely.
Video
Notes
APPLE BUTTER: You can use store-bought or homemade apple butter for these cookies. You can find apple butter in the jam/jelly/spreads aisle of the grocery store. Kroger or Mussleman's apple butter are great brands to try.
NO CHILL COOKIES: To bake these cookies immediately, bake at 350˚F for 13 minutes. Note: Cookies may be thinner than ones baked with chilled dough. Use a spatula to press the edges of the cookies inward just after the tray comes out of the oven to create thicker cookies.