In a small bowl, whisk together flour, baking powder, baking soda, salt, and spices until well blended.
In a large bowl beat butter, brown sugar, and egg on medium speed until well blended. Add molasses and vanilla, continue to mix until well blended. Gradually stir in dry ingredients until blended and smooth. Wrap dough in plastic and refrigerate for 1 hour.
Preheat oven to 375 degrees, Prepare baking sheets by lining with parchment paper or silpat.
Place the dough on a lightly floured surface. Sprinkle flour over dough and rolling pin. Roll dough to a scant 1/4-inch thick. Use additional flour to avoid sticking.
Cut out cookies with gingerbread man shape. Place cookies about 1 1/2-inches apart on baking sheet. (I put the sheet pan with the cookies on it in the freezer for 10 minutes to solidify the butter. Though you’re welcome to skip this step.) With a pastry brush, wipe off excess flour on cookies then add a thin layer of egg wash (lightly beaten egg). Decorate cookies with sprinkles while lightly pushing them into place.
Bake 1 sheet at a time for 7-10 minutes (7 minutes leads to softer cookies). Let cool on pan and enjoy! The can be frozen in a freezer bag for up to 3 weeks.