Place a parchment paper on the counter top for preparation. Set the baking cups on top. Melt chocolate in a double-boiler. Allow to cool slightly. In the meantime, combine the melted coconut oil and peanut butter. Add approximately one teaspoon melted chocolate to the bottom of each baking cup, followed by one banana slice, one teaspoon peanut butter mixture, and lastly drop about ½ teaspoon melted chocolate in the center of each cup. Carefully place cups on a freezer safe dish. Cover and place in the freezer until set and serve.