Combine dry ingredients. Whisk together flour, ginger, baking soda, cinnamon and salt in small bowl. Set aside.
Cream butter and sugars. With an electric mixer, beat butter, granulated sugar, and brown sugar on medium high until light and fluffy, about 2 minutes.
Add egg and molasses. Add the egg, mixing well until combined. Add molasses and mix just until combined. Scrape down the bowl as needed.
Add dry ingredients. Gradually beat in flour mixture. Chill the cookie dough for at least 1 hour, until firm.
Preheat and prepare cookie sheets. Preheat the oven to 375° F. Line two cookie sheets with parchment paper (or a silicone baking mat).
Scoop the cookies. Using a 1-inch cookie scoop or a tablespoon scoop the cookies into 1 ½ inch balls onto prepared cookie sheets about 2 inches apart.
Bake and cool cookies. Bake cookie sheet on the middle rack for 10-12 minutes, until lightly browned on the sides. The centers will still look soft. Remove from the oven and let cool on a baking sheet for 5 minutes before transferring to a wire rack to cool completely.