Every time I cut an onion I'm standing in the kitchen crying

Halfway through one onion and I can't see the knife. Somebody walked in and asked who died. — Home cook, 2017

Seed breeders spent about 30 years on this. They grew generations of onions and kept the ones that stung the eyes least. The result looks like any yellow onion but gets sweeter and gentler the longer it sits in storage, and it reached American stores in the winter of 2017–18. Here's the catch. It shows up around November, runs out by spring, and only some chains carry it. Outside that window you're on your own. Thirty years of work, and it's a winter onion.

For now: keep the knife sharp and cut slowly, since blunt, fast cuts throw more onion spray into the air. A sweet onion may sting less.

The full file

Here's where the crying comes from. Scientists had assumed the tear gas was a side effect of the onion's flavor chemistry. In 2002 a team at a food company in Japan showed that a separate enzyme makes it. They found it by accident. They were trying to build the stuff in the lab using an enzyme from garlic, and garlic doesn't make anybody cry.

The discovery won an Ig Nobel Prize in Chemistry in 2013. In 2002 one chemist wondered whether the tear gas is how an onion keeps insects and germs off, which would leave a tearless one easier to attack. Nobody has settled that.

Onions are old. People cultivated them 5,000 years ago or more, and a Sumerian text from about 2500 BC mentions a plow going through a city governor's onion patch. Somebody has been crying over them the whole time. The enzyme took until 2002, and the best fix took until 2018. Nobody hurried.