Preheat oven to 350 degrees. In a medium bowl, whisk together flour, baking soda, baking powder, and salt; set aside.
In a large bowl, using an electric mixer, beat butter and granulated sugar until light and fluffy. Add egg and vanilla; beat until combined. With mixer on low speed, add flour mixture; mix just until combined (do not overmix).
If using two colors of sanding sugar, place each in a separate shallow dish (or combine them in one). Roll dough into balls, using 1 1/2 tablespoons for each. Roll in sanding sugar, pressing lightly to coat completely. Insert a wooden stick in center of each ball; place on baking sheets, about 1 1/2 inches apart, with wooden sticks lying horizontally. Lightly press down on each ball with the bottom of a glass to flatten slightly.
Bake until edges are golden and crisp, about 20 to 25 minutes. Transfer cookies immediately to a wire rack to cool completely.