Anthony Bourdain's Crucial Advice For Slicing Onions

Slicing onions is one of those skills that often seems to separate the pros from all the rest of us home cooks. Chefs make it look easy, and can do it in super quick time. But, in your own kitchen, it's one of those tasks that can lead to tears. And not just because of the chemical release behind why onions make you cry; one slip of the knife on the cutting board, and you can get a nasty cut that elicits the waterworks, too.

There are plenty of tips and tutorials that offer advice and tricks to help. And then there's Anthony Bourdain to make it look especially serene and stress-free. The late chef and presenter's onion-slicing tips revolve around not only how to slice the alliums efficiently, but also how to reduce the risk of injury in the process.

One of the mistakes home cooks often make when cutting onions is extending their fingers and thumb forward to try to hold the onion still. But this can be dangerous, as it makes it easy to cut yourself with the sharp utensil. Instead, Bourdain recommends the tried-and-tested professional chef technique of keeping the fingers curled and the thumb tucked safely away from the blade, at an angle. This hand position means you can rotate the vegetable as needed, but it always keeps the precious digits away from the sharp edge of the blade.

While demonstrating how to slice onions on The Travel Channel, Anthony Bourdain started by peeling the onion, cutting off the top and bottom, and then slicing it in half to give a steady base on the cutting board. He then placed his hand at a 45-degree angle, with the tips of the fingers curled and the thumb tucked in, in what is known in culinary circles as a bear grip.

This chef's technique for holding the onion securely, cut side down, involves making slices top to bottom, almost but not right to the end of the onion at the root, which Bourdain kept intact. Then he made a horizontal slice through the onion half before rotating the veggie and slicing again to make a medium dice. The key is to keep the hand at a 45-degree angle throughout, with fingers tucked, and thumb safely out of the way.

Bourdain's technique, one that's used by many chefs, means that the knuckles are the only part of the hand to make contact with the knife as you slice. This vastly reduces the chances of a serious injury when slicing, dicing, or cubing vegetables for recipes. And it especially lessens the risk of doing "some serious damage" such as lopping off a thumb. The worst that can happen is you might nick the skin between the top and middle knuckles on the hand, which is holding the onion.

To slice or dice vegetables such as onions successfully, you need to start with a sharp knife. The sharper the knife, the easier it is to slice with, and there's less chance it will slip as you cut. And, a well-maintained blade also helps to lessen the chance of watery eyes, too as it does the job more efficiently. To keep the blade in top condition, a whetstone or sharpener is an easy way to upgrade your knife to prevent onion-induced tears.

Anthony Bourdain's tip to get better at slicing onions? "Practice, practice, practice, practice, practice" (as he shared on YouTube.) The late chef recommended buying some cheap onions or other hard vegetables such as turnips, and to keep trying the technique until you've mastered it.

Whether they're sliced, diced, or minced, it's best to use onions straight away once they've been cut, too. But, if you want to prepare a batch ahead, or you've got a bunch left after doing some chopping practice, then they can be kept in a sealed airtight container in the refrigerator for up to around four days.