Making banana bread from bananas is an ideal method of using overripe fruit. If bananas are plentiful and there is no immediate opportunity to whip up your banana bread, then freezing the bananas is the thing to do.
Peel the banana completely.
Inspect the banana for any bruising or other imperfections. Cut out any imperfections with the paring knife and dispose of them.
Place the banana into the plastic freezer bag.
Repeat steps 1-3 with two or three additional bananas. Seal each bag with the total of three or four bananas in it, as that is the amount of banana typically required to make one loaf of banana bread.
Write the current date on the bag and place it in the freezer.