Prepare cookie sheets by lining them with parchment paper.
Add room-temperature butter and sugar to a bowl and beat until creamy. (use a hand electric mixer or stand mixer fitted with the paddle attachment).
Add the egg, molasses, and vanilla and continue beating at medium speed.
In another bowl, add the flour, salt, baking powder, and spices and whisk until combined.
Slowly add the dry ingredients to the wet ingredients and continue beating until combined (scrape down the sides of the bowl as needed).
Transfer the dough to a work surface and press the gingerbread cookie dough onto two flattened discs. Wrap well with plastic wrap or place in an airtight container and refrigerate for at least 2 hours until firm or up to 2 days.
Use a rolling pin to roll the dough to a ¼ inch (6mm) thickness on a lightly floured surface (make sure to sprinkle a little flour on both sides of the dough to prevent sticking).
Use gingerbread man shapes to cut out the dough. Place on a prepared baking sheet and bake cookies at 350F for 8-12 minutes until the edges are golden brown.
Remove cookies to a cooling rack to completely cool before decorating. When cool, decorate them with my favorite easy icing.