Whisk dry ingredients in a medium bowl.
Beat butter and sugars in a large bowl with a mixer on medium speed until creamy, about 2 minutes. Increase the speed to medium high and beat until fluffy, about 2 more minutes. Beat in the egg and vanilla;
Reduce speed to low and mix in the flour mixture until just combined.
Put the sanding sugar and 1 tsp of cinnamon in a small bowl.
Use small cookie dough scoop to form dough into balls. Roll balls briefly over a damp paper towel then coat with cinnamon sugar before baking.
Bake about three inches apart on a baking sheet at 350 for 12 minutes. Let cool on a rack.