In a heavy duty blender or food processor, blend all ingredients until smooth and creamy. If necessary, allow bananas to thaw for 5 minutes before blending. Serve immediately**.
*Remove peel and roughly chop bananas prior to freezing. Freeze in a single layer on a parchment paper-lined baking sheet, then transfer to a freezer-safe container until you need them for this recipe.
**You can freeze leftovers, though the mixture will become a good bit harder. When you want to eat the leftovers, remove from freezer and let sit out at room temperature for 15 or so minutes.