Combine all ingredients (except the chocolate chips) in a medium sized bowl and stir until the mixture is smooth and creamy.
Pour peanut butter mixture into a 9 x 13 pan.
Melt chocolate chips in the microwave (at 50% power) for 1-2 minutes.
Stir chocolate, pour over the peanut butter mixture then spread with a spatula.
Put bars in fridge for one hour to set.
Cut bars once cooled.