Ripening an avocado can be done in the same way that you ripen bananas. Here’s how to ripen an avocado.
Place the avocado in a paper bag with an apple, banana, or tomato.
Fold the bag closed and leave it to sit on the counter overnight.
The ethylene gas in the other fruit will cause the avocado to ripen in about 24 hours.
If you don’t have other fruit to put in the bag with the avocado, you can put it in the bag by itself and it will ripen, but not as fast as if you’d put the fruits in with it.
Another method for ripening avocados is to bury them in a sack of flour overnight or place them in a paper bag with some flour. I haven’t tried this method but many people swear by it.
Happy avocado eating!