How to Cut an Onion

A step-by-step guide.

January 11, 2023

Related To:

Let’s be honest, no loves chopping onions. But if you learn how to do it properly, the job will be over much more quickly. Here, you’ll learn about the three most common ways to cut an onion: how to slice an onion, dice an onion and mince an onion. Plus, our best Food Network Kitchen-tested tip to avoid crying while you’re cutting onions (there are a lot of tips out there, but most of them don’t work!) and how to store leftover cut onion.

How to Cut Onions Without Crying

There are all kinds of tips on the Internet on how to avoid tears while cutting an onion. They range from lighting matches to putting bread in your mouth. We've tested every theory that exists and there are two that work well for us.

Method #1: Use a Really Sharp Knife

The first method is the simplest: use a really sharp knife. Not only does this make your job faster, but also it bruises fewer onion cells so less of the tear-causing enzyme is released.

Method #2: Freeze the Onion

The second method: put the onion in the freezer for 10 minutes before cutting. This doesn't change the flavor or texture of the onion; it simply reduces the amount enzyme is released.

How to Peel an Onion

Peeling an onion seems simple enough, right? You just...remove the peel. But what, exactly counts as the peel? Here, we get into how to peel an onion when the skin is too tight to grab, and just how much you should peel away and discard.

Do You Have to Peel Onions?

In most cases, if you're using cut onion, you'll need to peel the onion, as you will not be using the skin. If you're making stock, there's no need to peel the onion before adding it to the pot. You'll be discarding the whole onion after cooking, anyway, and the skin adds more flavor. Sometimes if you're roasting halved onions, you won't remove the peel either because it'll protect the onion from scorching.

Step 1: Cut the Onion In Half

If the root end of the onion is dirty, cut off just enough of the root to remove the dirty and wipe your knife clean. Cut off the pointy tip of the onion (on the side opposite from the root), discard the tip and place the onion cut side down. Cut the onion in half lengthwise, through the root end.

Step 2: Peel the Onion

Peeling both halves of the onion, even if you only use half, will make for easier chopping later. To peel the onion, grasp a corner of the papery outer layer near the onion's flat tip end. Firmly pull it off and remove it. If you're having trouble grasping it, trying sliding a paring knife underneath it. to pry it up. Don't remove any of the large onion layers below the paper; if some paper remains near the tip, slice off that area.

How to Slice an Onion

This type of cut onion looks like round flat slices of onion or half-moons. Use onion slices as salad toppings or ingredients, sauté them to make caramelized onions or add them to a stir-fry. Use round onion slices as burger toppings. Before diving into these instructions, make sure you follow the steps above to halve and peel your onion.

Step 1: Place the Onion on Its Flat Side

Place the flat side of the onion down to keep it from slipping.

Step 2: Slice Straight Down

For even onion slices, make a claw with your non-dominant hand and place your fingertips on the end of the onion. Rest your knife against the flat part of your knuckles and walk your fingers backward as you slice straight down through the onion half to create half-moons. The farther you move between slices, the thicker your onion slices will be.

How to Dice an Onion

Diced onion looks like evenly sized, small cubes of onion. Use diced onions in pasta sauces, salsas, home fries and soups. Before diving into these instructions, make sure you follow the steps above to halve and peel your onion.

Step 1: Place the Onion on Its Flat Side

Place the flat side of the onion down to keep it from slipping.

Step 2: Make Several Horizontal Cuts

Place your palm on the rounded side of one of the onion halves. Working carefully, hold the blade of your knife parallel to the cutting board and make several parallel horizontal cuts through the side of the onion, stopping right before the root end. Ideally, these cuts should be spaced 1/4 inch apart.

Step 3: Make Vertical Slices Across the Onion

Make vertical parallel slices evenly across the onion. Don't cut through the root; it helps hold the onion together as you chop. Ideally, these cuts should also be 1/4 inch apart.

Step 4: Make Vertical Crosswise Slices

Turn the onion 90 degrees, then make vertical crosswise slices. Try to make evenly sized cuts across so the diced onion is all the same size. Once you're done cutting, discard the root end.

How to Mince an Onion

Mincing onions is basically chopping onions as finely as you can. Minced onions can add zip to burgers, meatloaf, salad dressings or dips. Rinsing minced onions with cold water makes them less potent. Before diving into these instructions, make sure you follow the steps above to halve and peel your onion.

Step 1: Start with Diced Onions

Proceed through steps 1 through 4 above!

Step 2: Chop the Diced Onions

Lay one hand flat across the tip of your knife and use a rocking motion to chop. Keep going until the onions reach an evenly sized fine dice.

How to Store Cut Onions

Wrap cut onions tightly in plastic wrap or transfer them to an airtight container to the refrigerator for up to one week. For more info on how to store onions, including uncut onions, check out our story How to Store Onions.

Related Links:

Next Up

How to Caramelize Onions

Yes, there’s some technique involved. But we break it down into steps and arm you with a number of smart tips.

White Versus Yellow Onions: What's the Difference?

A guide to 7 different types of onions.

What Is a Clove of Garlic?

And here's how much garlic powder you should substitute per clove.

How to Roast Brussels Sprouts

Right this way for golden, crispy perfection.

How to Make Roasted Delicata Squash

Yes, you’re supposed to eat the skin. You can eat the seeds, too.

What Is Hubbard Squash? And How to Cook It

Inside the bumpy, thick skin there's a surprise.

What Is Tomato Paste?

Everything you need to know about this pantry staple.

How to Peel Garlic

Here are five different techniques depending on how much garlic you need to peel.

How to Steam Broccoli In the Microwave

It takes about 3 minutes and there’s no oil necessary.

Is It OK to Eat Brown Guacamole?

Here’s why guacamole quickly turns brown.

More from:

Cooking School

What's New