Preheat oven to 350°F. Line a baking sheet with parchment paper or a baking mat.
In a stand mixer cream the butter, brown sugar, and sugar on medium speed for 2 minutes. Add the eggs and vanilla and beat until fully combined.
Add the cocoa powder, flour, baking soda, and salt. Mix until partially combined. Add the peanut butter chips and mix until just combined.
Portion the dough into 1/2 cup balls. Press down on the balls with your palm to resemble a hockey puck. Bake for 9-12 minutes.
Remove from the oven and let cookies sit on the baking sheet for 5 minutes before transfer to a wire rack. Enjoy warm or at room temperature.
Notes
Storing and Freezing: Store the cookies in an airtight container or Ziplock bag at room temperature for 3-5 days.For freezing, I would recommend freezing the dough instead of freezing the baked cookies. Freeze the dough balls in the freezer on a baking sheet until set/solid. Then transfer to a ziplock bag or airtight container. Cookie dough will keep in the freezer up to 3 months. Remove from the freezer and bake from frozen. You may need to add an additional minute or two onto the bake time.