Preheat oven to 350°F (175°C) and line baking sheets with parchment paper.
Sift together flour, ginger, baking soda, cinnamon, and salt.
Beat butter and sugar until light and creamy, then add egg and molasses.
Mix dry ingredients into wet mixture until dough forms.
Roll into 1-inch balls, coat with cinnamon sugar, and place on baking sheet.
Bake 10 minutes until tops crack. Cool on wire rack.
