Put Them Next to Other Fruit
You’ve probably been warned not to store bananas next to apples or similar fruit. Well, this time, that’s exactly what you should do. Apples, avocados, melons, and other high-ethylene-producing fruit can ripen your bananas faster than if you left them on their own.
Bake or Microwave Them
Although it may sound extreme, baking your bananas can give them the soft texture of naturally ripe bananas. Microwave them for about 25 seconds or bake them in your oven at 300°F.
Put Them in a Paper Bag
This method combines the previous two and might even be easier to execute. You’ll only need a paper bag and a warm environment. The bag will trap the ethylene bananas produce and keep it in that environment for longer. To speed up this process, you can add ripe bananas or apples to the bag.
Freeze Them
Cold temperatures help the cells and starches in bananas break down faster and give them that ripe look. The downside to this method is that it’s not the fastest. You need to wait for the bananas to freeze and then defrost, but it can act as your last resort.