Cream together the butter and sugar in a large bowl (the bowl of a stand mixer), or with a hand mixer until light and fluffy, about 2 minutes. 1 cup unsalted butter , 1 cup granulated sugar
Add the egg and vanilla extract and mix until combined, scraping the edges and side of the bowl as needed. 1 large egg, 2 tsp vanilla extract
Add in the flour, cocoa powder, baking powder, and salt and mix until combined and you have a nice soft dough. (It will look crumbly at first then will start to come together). 2 1/2 cup all purpose flour, 6 TBS unsweetened cocoa powder, 1/2 tsp baking powder, 1/2 tsp salt
Roll the cookie dough out on a lightly floured counter top to be 1/4 inch thick.
Cover the dough with parchment paper on top and bottom and place it in the fridge for 1 hour.
Remove from the fridge and cut the cookies out into desired shapes.
Place the cookies onto a lined cookie sheet about 1 inch apart.
Place the cookie sheet in the fridge to chill for another 15 minutes.
While chilling, preheat the oven to 350 degrees Fahrenheit.
Continue rolling and cutting out additional cookies, pressing the scraps of dough together as needed.
Place one pan of cookies into the oven at a time and bake for 7 to 8 minutes, for 2 to 3 inch cookies, or until the tops of the cookies are no longer shiny, and the cookies look set.
Remove the pan from the oven and let the cookies sit on the cookie sheet for at least 5 minutes to chill.
Transfer the cookies to a cooling rack to cool completely.
Enjoy unfrosted, or frost and decorate as desired.