Cook in microwave for about 30 seconds. If mixture is not melted, cook for an additional 10 seconds. Stir melted chocolate and oil until combined.
Pour about 1 tsp chocolate into silicon muffin molds. Carefully swirl chocolate up the sides of the mold. Place molds in freezer for about 10 minutes.
Remove from freezer and gently spoon in banana mixture into each mold.
Top with remaining chocolate and return to freezer for about 20 minutes.
Carefully pop out the chocolate cups from the molds and serve!
You can easily use sunflower seed butter or another nut butter alternative if necessary.