In a medium bowl, combine flour, cocoa powder and baking powder with a whisk. Set aside.
Using a hand mixer or a stand mixer fitted with the paddle attachment, beat the butter and salt on medium speed until combined, about 1 minute. Add in sugar and beat until smooth, about 1-½ minutes. Beat in vanilla and eggs, one at a time, and mix until well combined. It may take a few minutes to fully incorporate both eggs. Scrape up and down the sides of the bowl as needed.
With the mixer on low, add the flour mixture a little at a time, occasionally stopping to scrape your bowl. The dough will start to form a ball around the paddle when the mixing is finished. The dough should be soft and a little sticky.
Wrap the dough ball in plastic wrap and press into a 1 inch thick disc. Chill for a minimum of 30 minutes before rolling and up to seven days.
Preheat the oven to 375°. Prepare baking sheets with silicone baking mats or parchment paper.
On lightly floured surface, roll the dough to about a ¼ inch thickness, use additional flour as needed to prevent sticking. Cut into shapes with cookie cutters. Re-roll the remaining dough and continue cutting until all is used.
Arrange cookies on baking sheets about 1 inch apart.
Bake one sheet at a time in the middle of the oven, about 7-8 minutes, until puffy. Allow the cookies to rest for 2 minutes on the pan and then transfer to a wire rack to cool completely.
Notes
Decorate as desired.Yield of cookies will depend on the size of your cookie cutter. 24 is a good average.Cookies will stay fresh covered at room temperature or in the refrigerator for up to 1 week. They also freeze well for up to 3 months.