Line a 9x13 inch baking pan with parchment paper and set aside.
In a large bowl, cream together the butter, peanut butter and vanilla until smooth. Add in the powdered sugar, and mix until fully combined.
Spread the mixture evenly over the prepared baking pan, pressing down with a silicone spatula. Place in the fridge.
In a microwave safe bowl, microwave the chocolate chips and coconut oil in 30 second intervals, mixing until smooth.
Pour the melted chocolate overtop the peanut butter mixture and smooth with a spatula. Return to the fridge until the chocolate has hardened. Cut into bars.