Preheat oven to 350 degrees. Line a 9x13 baking dish with aluminum foil and spray with PAM. In a large bowl cream together butter and sugar; Add salt, eggs and vanilla and continue beating until combined. Add in flour and cream of tartar mix until blended. Scoop dough into baking pan and smooth into an even layer.

Topping: stir together sugar and cinnamon and sprinkle over dough. Bake 32-35 minutes until edges are lightly browned and bars are set. Cool before serving.