Preheat the oven to 375ºF. Line baking sheets with parchment paper.

In the bowl of a stand mixer (or using a mixing bowl with an electric mixer), cream the shortening and the sugar until well mixed, scraping the sides of the bowl as needed.

Add the eggs and mix again until combined.

Add in the flour, cream of tartar, baking soda and salt. Mix well until combined.

Roll the cookie dough into balls.

In a small bowl, combine the sugar and cinnamon. Roll each cookie dough ball in the cinnamon sugar mixture, then place on the baking sheet.

Bake for 8-10 minutes. Don’t let the cookies get brown if you’d like them to be soft.

Right after they come out of the oven, swirl in a mason jar ring or round cookie cutter so that they are perfectly round.