In a medium bowl, combine dark chocolate chips and coconut oil. Heat in 30 second intervals in the microwave stirring well after each until chocolate is melted and smooth.
Pour one tsp of chocolate into the molds.
Heat peanut butter in the microwave for a few seconds. Just enough to make it smooth and easy to spoon out,
Measure ½ tsp of peanut butter into each mold on top of chocolate.
Place in the fridge or freezer for a few minutes until it sets.
Add another tsp of chocolate on top of the peanut butter, creating a peanut butter cup. Allow to sit at room temperature or place in the fridge or freezer until fully set.