Avocados are perfect to spread on toast or put in tacos but can often take a while to ripen. It can be frustrating to buy one before having to week a week for it to be ready to be eaten.

While some people may opt to put their avocados in the microwave as a quick solution to ripen them, there is a more effective method. Although heating your avocados can cause them to turn mushy and unpleasant to eat, putting them in a bag with one other fruit makes them ripen quickly while maintaining their delicious flavour. A chef from America's Test Kitchen said the method is easy and leaves people with perfectly ripe avocados.

Kate Bernot recommends people to simply place their unripe avocados inside a bag with a banana. To further speed up the process, move the bag to a warm spot in your kitchen.

She said: "I tried this with one of the fist-sized rocks my grocery store sells as avocados, plus two ripe bananas. Less than two days later, I had taco-ready, ripe avocados. (My husband thinks I possess magic fruit-ripening powers, but I actually just used simple science)."

The method works as bananas produce a lot of ethylene gas. This causes the avocadoes to convert their starches to sugar which speeds up the ripening process.

The bag helps to trap the gas, which makes the process quicker, often ripening avocados within 1-3 days. Experts say you can also use apples or kiwis as they also release ethylene.

To tell if your avocado is fully ripe, Kate recommends pressing the bottom of it - the fat and round end. If this part feels ripe and squishy then the rest of it will be too.

She explained the process: "To ripen an avocado using a banana, simply place unripe avocados inside a paper bag with a banana or two. This speeds up the ripening process. Moving the bag to a warm spot in the kitchen can add a further ripening boost."

She added: "Avocados are what’s called climacteric fruits, meaning they become ripe after they’re picked when the ethylene gas level inside them reaches a certain point.

"Ethylene gas acts like a plant hormone, signaling to fruit that they should put a little pep in their step when it comes to ripening. As one piece of fruit emits ethylene gas, other climacteric fruits nearby get the message that it’s time for them to ripen, too.