Preheat the oven to 350 degrees
Pour the chocolate cookie mix into the bowl of your mixer.
Add the butter and egg, well mixed.
Once the butter and egg is well-combined add in the peanut butter to the mixture.
Spoon 1 inch balls on to an ungreased cookie sheet.
Bake for 8-10 minutes, do not over bake. The cookies will continue to bake on the sheet pan so don't worry if they don't look completely baked.
Once cooled store in an airtight container.