Preheat oven to 400 degrees
Cream the shortening and sugars together.
Add eggs one at a time and beat thoroughly.
Sift together the flour, salt, cream of tartar, and baking soda.
Gradually add to the buttered mixture beating well after each addition.
Cover dough with plastic wrap and chill in the fridge for 30-45 minutes.
While dough is chilling combine cinnamon and sugar in a medium size bowl.
Roll dough into balls, about the size of walnuts and then dip in the cinnamon sugar mixture.
Place on a baking sheet lined with parchment paper.
Bake for 8-10 minutes until crinkled and lightly browned, but still soft.
Remove from oven and place pan on wired rack for 2 minutes.
Remove from pan and place on wire racks to continue to cool.