Stir dry ingredients together and set aside.
Cream butter and sugars together until light and fluffy. Beat in the yolk and vanilla. Add molasses and beat again, scraping the bottom of the bowl.
Stir in the flour to make a soft dough. (Add a little flour if needed to handle the dough.)
Roll the dough into 1 inch balls. Dip the tops in coarse sugar and set on a baking pan, sugar side up.
Bake at 375°F for 8-10 minutes. Do not overbake. Allow cookies to rest on the pan for 2 minutes before transferring them to a wire cooling rack to cool completely.