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This post is about how to cut an onion.
The number one question I get asked in my cooking classes is, “How do you cut an onion?”
I get it. Onions are tricky. Not only do onions have the ability to make you sob uncontrollably when you cut them, but it can fall apart if you cut the onion the wrong way. You find yourself chasing bits of onion around on your cutting board as you are chopping and sniffling, pushing through the pain. Inevitably, you go to rub your eyes to wipe away the tears, and moments later, you realize your mistake — and feel the BURN.
Learning how to cut an onion the right way is one of the first things they teach you in culinary school. There are many different ways to cut an onion, and depending on which chef you ask, they will all tell you that their way is the easiest way to cut an onion.
In this guide, we will talk about the correct way to slice an onion, which end of an onion you cut first, the first step to cutting an onion and cooking tips on how to not cry when cutting onions. In no time, you’ll be chopping onions fast like a chef.
This post is all about how to cut an onion.
WHY DO ONIONS MAKE YOU CRY?
Cutting onions releases chemicals that irritate your eyes. Primarily, these chemical compounds are sulfur-containing molecules known scientifically as lachrymatory factor, or “LF”. When the onion is cut, the cell wall is “damaged”, triggering a stress response from the onion to release sulfuric LF molecules in the air.
The onion’s sulfur travels through your nose and to your eyes, coming in contact with the moisture in your eyes. Sulfuric acid is created, irritates the eyes, and triggers you to cry. This is your body’s response to dilute and flush out the sulfuric acid, causing irritation and discomfort.
As you continue to slice the onion, more of these sulfur chemicals are released. This continues to intensify your body’s response to cry.
HOW TO CUT AN ONION WITHOUT CRYING
Unfortunately, there is no way to 100% guarantee zero tears when working with onions. However, there are many ways to minimize crying when cutting an onion. The first of which — putting your onions in the freezer 30 minutes before you plan to use them.
Why on earth would I recommend this? The enzymes and sulfur in onions trigger a chemical response in our eyes, responsible for making us cry. By cooling the onions, you are slowing down the process of the onions releasing these enzymes and sulfur that they would at room temperature. Putting the onions in the refrigerator or freezer before slicing them will slow down the reaction of the sulfur being released.
You can also achieve this same result by dunking the onion in an ice bath for 10 minutes prior to cutting the it. Whichever way you choose to go about it, getting the onion cold will help prevent eye irritation because you are reducing the quantity of chemicals released by the onion when it is cut open.
However, don’t store your onions in the refrigerator as they absorb moisture. The moisture in the air in your refrigerator can get trapped under the papery skin of the onion which makes them get mushy and spoil faster.
The second biggest tip for cutting an onion without crying, is to use a sharp, high-quality chefs knife. My all-time favorite chefs knife is the Mac MTH-80.
DOES CHEWING GUM HELP WHEN CUTTING AN ONION?
There are several other ways to not cry when cutting an onion. I’ve heard people recommend chewing gum, burning a candle nearby, or even running water from your sink will prevent you from crying when cutting an onion. None of these techniques work nearly as well as chilling your onions.
I’ll start by debunking the gum chewing. In professional kitchens, it’s unsanitary to chew gum while prepping food items, so this would never be an option for chefs. However, for the home cook, this may be helpful, as chewing gum can lessen the blow the enzymes in the onion have on your tear ducts. However, the chemical reaction is triggered in your eyes, not your nose or mouth, which means there is still a high probability of you crying when cutting onions.
Burning a candle while chopping onions can help prevent you from crying, as the flame helps burn off the sulfur compounds produced by the onion. Running water can also lessen the amount of sulfur that makes it to your eyes as it travels in the air. The sulfur in the lachrymatory factor can still travel through your nose and to your eyes and trigger the tear response, even with running water.
HOW TO CUT AN ONION FOR BURGERS
Start by peeling the onion, remove the outer skin of the, and cut off the top and bottom ends to discard them. Peel off the papery outer layers until you reach the fresh, clean layers underneath. I like to remove the first layer of the onion as well as it tends to be thin and flavorless.
Place the onion on its side on a cutting board and use a sharp knife to slice the onion crosswise into thin rings. The goal is to get slices that are about 1/2 inch thick. Once you’ve sliced the onion, gently separate the rings from each other. Do this by pulling the onion layers apart with your fingers and using the tip of the knife to loosen any rings that might be stuck together. If you plan to cook your burgers on the grill, read up on grilling for beginners tips.
HOW TO CUT AN ONION INTO STRIPS
The best way to cut an onion into strips starts with peeling the onion. Cut the onion in half from top to bottom, slicing through the root. Cut off the tops and bottoms of the onion halves. Place one half of the onion flat side down on the cutting board and slice it vertically through the onion. Make sure that all your slices are consistent in thickness for even cooking. Repeat this for the other half of the onion. This is the best technique for french onion soup.
HOW TO DICE AN ONION PROPERLY
Dicing an onion properly requires uniformity in your knife cuts and precision of knife skills. First start by prepping and peeling the onion. Cut off the stem end, but leave the root end intact, as this helps hold the onion together as you dice.
Take one half of the onion and place it flat side down on the cutting board. Place the palm of your non-dominant hand on the top of the onion with your fingers extended so you don’t slice yourself. Take the edge of the blade and begin to make horizontal slices into the onion. Start at the base of the onion against the cutting board (the widest part of the onion). Move the blade slowly towards the root, being sure not to slice through it; this keeps the onion intact. Repeat these horizontal slices about a 1/4 inch apart, working your way up the onion, towards the palm of your hand.
Make your vertical cuts by rotating the onion 90 degrees. Hold the onion together with the “3 finger knife rule”, using your pinky and thumb to grip the sides of the onion. Again, start at the root end and work towards the stem end, not cutting all the way through the root. Now, you can create your dice. Continue to hold the onion together with the “3 finger knife rule” — one of the basic ways to improve your knife skills. Make downward cuts, horizontal to the root of the onion. You’ll see that the onion falls away, into a small uniform dice. Discard the root of the onion.
HOW TO CUT AN ONION FOR FAJITAS
The first step to cutting an onion for fajitas, is to peel the onion. Remove the papery outer layer of the onion and cut off the top of the onion. Leave the root end of the onion in place, as this holds the onion together. Cut the onion in half lengthwise, from top to bottom, slicing through the root. You should now have two halves.
Place one half of the onion flat side down on the cutting board and slice it horizontally across the onion. Make sure that all your slices are consistent in thickness for even cooking. Repeat this for the other half of the onion.
HOW TO PEEL AN ONION QUICKLY
You can peel an onion quickly by cutting off the top stem end of the onion. Leave the root end (the “hairy” part) intact as this helps hold the onion together when you cut it. Score the onion with the tip of the blade, just going through the top papery layer. You should be able to easily peel off the outer layer, working your way around the onion until all the skin is removed. This is easier to do using a pairing knife or a utility knife. I like this utility knife, not only for onions but also for slicing delicate tomatoes.
HOW TO CUT AN ONION Q&A
Do you cut all the way through an onion at first?
Unless you want to cut rings of your onion, you should cut through the root and top of the onion to get two halves.
Do you cut all the way through an onion at first if you are chopping it?
A good rule of thumb is to keep the root of the onion intact to ensure the onion does not fall apart as you are chopping it.
How do you make it easier to cut onions?
I always put my onions in the refrigerator before I cut them to make it easier. It helps to slow down the sulfur enzyme from being released and making you cry.
What is the first step when cutting an onion?
Always peel your onions before cutting them. The papery outer layer of. the onion is inedible.
Which end of an onion do you cut off first?
Cut off the top stem of the onion, but leave the root (the “hairy” end) intact.
How to cut a red onion?
You can cut a red onion the same way you would cut a yellow or white onion.
How to not cry when cutting onions?
The best way to not cry when cutting onions is to put them in the refrigerator or freezer for 30 minutes prior to slicing. This slows down the release of the sulfur enzyme that is released from the onions and causes irritation to the eyes.
What is the correct way to slice an onion?
No matter which way you choose to slice an onion, you should always leave the root end intact.
