1. In a mixing bowl, beat shortening with an electric mixer on medium to high speed for 30 seconds. Add the brown sugar, granulated sugar, baking soda, cream of tartar, and salt. Beat until mixed. Beat in the egg and vanilla until the mixture is combined. Beat in as much of the flour as you can with the mixer. Stir in any remaining flour with a wooden spoon.
2. Shape into 1-inch balls. Roll in 1/2 cup granulated sugar to coat. Place 2 inches apart on a greased baking sheet.
3. Bake in a 375 degrees F oven for 8 to 10 minutes or until golden brown. Remove cookies and cool completely on a wire rack.