Combine the ingredients for the coating in a shallow bowl. Set aside while you make the cookies.

Whisk together the flour, baking soda, ginger, cream of tartar, and salt. Set aside.

Using an electric mixer on medium speed, beat the butter, brown sugar, and sugar until light and fluffy. Add the eggs one at a time, mixing well after each addition. Mix in the vanilla.

Reduce the mixer speed to low. Gradually add the flour mixture, mixing just until combined.

Cover and chill the dough for 1 hour.

Using a tablespoonful of dough at a time, roll the dough into balls and then roll each one in the sugar coating. Place the cookies on the prepared pans, leaving about 2 inches between each cookie. (If your kitchen is warm or your hands were warm while shaping the dough, place the pans in the refrigerator for about 15 minutes.)

Bake (one pan at a time) 8 to 10 minutes, or until the cookies are lightly browned and set.

Place the pans on a wire rack and allow to cool for 10 minutes. Then transfer the cookies from the pan directly onto a wire rack to cool completely.