It's rare, but every so often, not all of the bananas get eaten before they start getting too soft. Don't spend a moment feeling guilty; the best solution is to peel them (if you don't, you'll have to shave off the peel once frozen), slice them (if you can, or just break up into mushy bits), and freeze in a plastic freezer-safe container, plastic bag, or wrapped in wax paper. Next time you have a hankering for a smoothie, you have the perfect ingredient waiting for you in your freezer: already frozen pieces of banana.
This also works well for other tropical fruits like mangoes, papaya, and pineapple, stone fruits like peaches, nectarines, plums, apricots, and cherries, and also for berries.
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