Line a baking tray or plate with parchment paper or wax paper.
Add the chocolate chips and coconut oil to a microwave-safe bowl.
Microwave for 30 seconds, stir, then continue heating in 30-second intervals, stirring after each, until completely smooth and melted (about 1½–2 minutes total).
Slice the bananas into ½-inch thick rounds.
Using a fork, dip each banana slice into the melted chocolate until fully coated.
Allow any excess chocolate to drip back into the bowl.
Arrange the coated banana slices on the prepared baking tray.
Sprinkle with flaky sea salt if desired.
Freeze the Frozen Chocolate Banana Bites for at least 2 hours, or until completely firm.
Serve straight from the freezer and enjoy.