How to Cut an Onion

How To Cut an Onion

The first thing to consider when cutting an onion is it’s cell structure. The more you mess with it, the more it messes with you. If you would like to complete the job of cutting an onion tear-free then this lesson is for you. I’m assuming everyone does…. unless you are prepping for an acting job!

First take a look at your onion, one end is the root and the other is the stem. Onion cells are longer in the pole-to-pole direction, meaning from root to stem or the direction that they grow. Thus, if you cut the onion in this direction you are damaging a fewer number of its cells. If you damage less cells, then less of its ‘tear gas’ will be emitted toward your eyes. You will still get plenty of onion flavor from an onion cut pole-to-pole, but it won’t be overpowering.

To accomplish the feat of cutting an onion without tears, a little planning is necessary:

1. Refrigerate the whole onion for at least 30 minutes before cutting, slicing and/or chopping. The cold refrigerator actually chills the sulfur compounds in the onion, which is what causes the eye irritation in the first place.

2. Remove the outermost layer of the onion and then cut off the stem.

3. Stand the onion on the cut end and slice the circle in half.

4. Place your knife tip just shy of the root, again with the cut side face down, and chop down through each half from rounded root end to cut flat end, this will keep all of the slices still attached at the root. When you let go, the onion will fall to it’s side like a flower as shown. Simply slice off the root end at this point. Repeat this step with the other onion half. When you cut an onion this way it will hold together (before detaching the root) to dice your onion, if you’re going the extra step after slicing your onion.

5. Your slices will look like the onion on the left, not orbital around the circumference like the one on the right. Onions sliced in the manner described will also be nice and tender in your soups or stews. Onions sliced orbitally can become almost like worms when cooked, definitely a less desirable texture.

6. The only time that you may want to slice an onion orbitally is when making thin slices for sandwiches, as they do look prettier and lay nicer inside a burger bun when they are sliced orbitally.

If in England, look for Sweet Red Onions which were bred without lacrimatory-factor enzyme – supposedly making them tear free!

Additional Information

For more on onions, see our onion varieties post or our how long onions last page.