Preheat the oven to 350F then line a baking sheet with parchement paper and set aside.
Cream the butter, granulated sugar, and brown sugar together until light and creamy. Add in the egg, vanilla extract, and mix until smooth.
Gently mix in the flour, corn starch, cream of tartar, baking powder, baking soda, cinnamon, & salt until the flour mixture disappears.
Scoop out equally sized cookie dough balls, gently flatten them n between the palm of your hand and place the fozen Nutella in the center. Gently fold the cookie dough over it. Roll the dough in between the palm of your hand, then roll in the cinnamon-sugar mixture, place on the baking sheet. (Read make the cinnamon-sugar mixture below to see how to make it)
Bake the cookies in the preheated oven for 12 minutes then let the cookies sit on the baking sheet until fully cool.