After 30 minutes or so, make the chocolate layer: Add chocolate chips and coconut oil to a microwave safe bowl and microwave on high in 30 second increments, stirring in between until chocolate is completely melted. If you prefer, you can also melt the chocolate and coconut oil in small saucepan over low heat.
These healthy peanut butter twix bars should be kept covered in the fridge until you're ready to serve them. They will stay good in your fridge for about 1 week, but you can also keep them in a freezer-safe container in your freezer for up to 1 month.