Onions are notorious for becoming mushy and sprouting legs before you've had time to use them up but it turns out that storing onions with one everyday kitchen staple can dramatically extend their shelf life, helping you to avoid food waste and to save money.

A food storage expert exclusively told Express.co.uk that the key isn’t fancy gadgets or special containers, but rather ensuring onions get plenty of airflow while staying in a cool, dark, dry spot. So where – and with what – should you store onions?

Food expert Sophie Trueman at Too Good To Go says: "Keep whole onions in a cool, dry, dark spot with good airflow. A cupboard works well."

And when it comes to which item to store onions with, Trueman revealed "paper bags" enable the onions to "breathe".

Onions should also be stored away from potatoes, which Trueman revealed would only "speed up spoilage". 

Is this true for all onions?

Trueman points out that red and yellow or white onions can be stored the same way, though red onions may soften a bit quicker.

For cut onions, the rule changes: "Once cut, pop them in a sealed container in the fridge and use within three to five days."

When it comes to deciding whether to keep or toss your onions, Trueman encourages us to trust our senses before throwing them out.

"Take a moment to look, smell and taste," said Trueman, adding that you should take note of any sprouting, dry skin or slight softness. 

If the onion feels slimy, has mould, or smells off, it’s best to let it go. For those wanting even more practical tips on reducing kitchen waste, Trueman recommends downloading the Too Good To Go app, a helpful resource for saving good food from going to the bin.