01 - Line a baking sheet with parchment paper.
02 - Slice bananas into ½-inch thick rounds and arrange in a single layer on the prepared baking sheet.
03 - Place banana slices in the freezer for at least 1 hour until firm.
04 - Melt dark chocolate and coconut oil (if using) together in a microwave-safe bowl in 20–30 second increments, stirring between each, or melt over a double boiler until smooth.
05 - Using a fork or toothpick, dip each frozen banana slice into the melted chocolate, coating thoroughly.
06 - Place chocolate-coated banana bites back on the baking sheet and immediately sprinkle with chosen toppings before the chocolate sets.
07 - Return the tray to the freezer for at least 1 more hour until the chocolate hardens.
08 - Serve frozen; store leftovers in an airtight container in the freezer for up to 2 weeks.