If your bananas are yellow and green and you need to ripen them quickly for a Banana Loaf then you will need to do the following.
1. Heat the oven to 150°C, Gas Mark 2 or 300F.
2. Place the whole bananas including their skin onto a lined baking tray in the middle of the oven.
3. Bake them for approximately 20-30 mins or until they turn black and are very soft to the touch.
(A lined tray is used in case the banana skin splits whilst baking). I baked mine for approximately 23 mins.
4. Once fully black remove from the oven and allow to cool for 5-10 minutes. The bananas will then be fully ripened and ready for you to use.
5. You can then snip off the end of the banana skin with scissors and squeeze out the gooey ripened banana contained inside directly into your banana loaf cake batter.
Another way of ripening bananas albeit slowly is to place them on top of other fruits in a fruit bowl such as apples. When bananas come into contact with other fruit it speeds up the ripening process hence the reason they go browner more quickly. This option will take a few days for the bananas to fully ripen and turn brown.