*chop peanut butter cups to the approximate size of chocolate chips
Combine butter with brown sugar and white sugar until well incorporated. Stir in egg and vanilla extract. In a separate bowl, combine baking soda, Kosher salt, and cocoa powder. Add to wet ingredients and stir until just combined. Gently fold in chopped peanut butter cups.
Using heaping tablespoons, drop cookies onto ungreased sheet pans and bake in a preheated 350°F oven for approximately 10-12 minues.