In a large bowl, whisk together the dry ingredients - flour, cocoa powder, baking powder, and salt. Set aside.
In a separate mixing bowl or a stand mixer with a paddle attachment, cream together softened butter, packed brown sugar, and granulated sugar on medium speed for about 2 minutes or until fluffy. Add one egg, and beat until combined. Then, add one more egg and vanilla extract, and beat until combined. Don’t forget to scrape the bottom and the sides of the bowl to make sure everything is combined well.
Add the dry ingredients to the wet and mix on a low speed until just combined. Don’t overmix. Then, stir in chocolate chips using a rubber spatula. The mixture should be sticky. Cover the bowl with plastic wrap and let the batter chill in the refrigerator overnight or for at least 4-5 hours.
When ready to bake, prepare the oven to 350 F. Line two large baking sheets with parchment paper.
Scoop the dough and roll it out into 1-inch balls using your hands (if the dough is too sticky, lightly wet your hands or use a cookie scoop). Lightly roll in granulated sugar. Then, generously roll in powdered sugar. This will prevent the powdered sugar from being absorbed into the batter. Repeat with the remaining cookie dough. Arrange the balls on the prepared baking sheet, leaving about 2 inches between each cookie. Bake in the preheated oven for 11-13 minutes or until they have firm edges but soft center. Remove from the oven, land et the cookies cool for 5 minutes on a baking sheet. Then, transfer to a cooling rack. Enjoy!