01 -  In a large mixing bowl, combine softened butter and sugar until light and fluffy. Gradually mix in the eggs, one at a time. 
 02 -  In a separate bowl, sift together the flour, cream of tartar, and cinnamon. Slowly incorporate into the wet mixture until a smooth dough forms. 
 03 -  Cover the dough with plastic wrap and refrigerate for 30 minutes to make it easier to handle. 
 04 -  Preheat the oven to 180°C (350°F) and line a baking tray with parchment paper. 
 05 -  Shape dough into small balls (approximately 20g each). Roll each ball in a mixture of cinnamon and sugar. 
 06 -  Place the coated balls on the prepared baking tray, spacing them evenly. Bake for 10-12 minutes or until the edges are lightly golden. 
 07 -  Let the cookies cool on a wire rack before serving. Enjoy!