When my bananas get over ripe, I freeze them in their skins. I sometimes buy extras if the price is right. The skin will get black but the fruit is still perfect. When I make a smoothie I just take a banana out and puree it with whatever fruit and you don't need any ice and there is no dilution. I have them a few days a week. Or buy strawberries frozen in the bag and just add them to the same effect.