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Dice an Onion in Under a Minute with This Foolproof Method

Diced onion on a cutting board with a few onions and a small chef's knife in teh background.
Emilee Unterkoefler / LifeSavvy 

Dicing an onion is a basic skill, but not everyone knows how to quickly achieve uniform results. Here’s how to dice an onion fast and furious, with no fuss.

Some recipes call for a rough chop rather than a uniform dice, but did you know they’re technically two different types of cuts? No worries if you didn’t; we’ll show you the difference below.

What’s the Difference Between Chopping and Dicing?

A cutting board with two small piles of onion displaying what chopped onion and diced onion looks like.
Emilee Unterkoefler

Chopping means cutting something in similarly sized pieces, while dicing involves cutting something (like an onion) into uniform pieces. A diced ingredient will typically take on a small cube-like shape.

So next time a recipe calls for chopping something up, don’t worry too much about appearance. When a recipe calls for dicing, that’s where precision matters, but not only for appearance.

The evenly cut and sized pieces will make or break the texture and how the meal all-around comes together.

If you want to get a little more technical, you can look at the three main dice sizes:

  • Fine Dice: (Also called a brunoise dice) measures about 1/16 of an inch is sized just right for risotto and rice.
  • Small Dice: Measures about 1/4 of an inch and is great for soups and chowders.
  • Medium: Measures about 1/2 of an inch and is sized perfectly for hearty stews.
  • Large: Measures about 3/4 of an inch and fits in dishes that simmer for several hours.

How to Dice an Onion

Dicing an onion is a quick and easy process. Once you learn how to do it correctly, you’ll be dicing in under a minute! Be sure to grab a sharp chef’s knife and a stable cutting board first, though.

Follow these steps:

Slice the stem end of the onion off, leaving the opposite end (called the root end) on. Keeping the root side on does two things. It helps keep the onion intact when you slice and prevents the onion from bleeding and you from crying.

Slicing the stem of an onion off.
Emilee Unterkoefler

Cut the onion in half, and then peel back the first layer.

Slicing an onion in half before peeling it.
Emilee Unterkoefler

Make evenly spaced vertical slices in your onion, coming as close as you can to the root but without slicing through it.

Slicing an onion multiple times vertically with a few onions and peels in the background.
Emilee Unterkoefler

Carefully run your sharp chef’s knife sideways to make a few horizontal slices.

Slicing an onion horizontally a few times before dicing.
Emilee Unterkoefler

Hold the onion with your fingers curled inward, and start making evenly spaced slices. Watch as the uniform pieces fall on your cutting board.

Dicing an onion in uniform peices with peels and onions in the background.
Emilee Unterkoefler

Look at that nice dice!

If this motivates you to practice those knife skills, you might end up with an overabundance of diced onions. Lucky for you, diced or chopped onions (and a few other veggies) freeze really well.

Emilee Unterkoefler Emilee Unterkoefler
Emilee Unterkoefler is a freelance food writer, hiking enthusiast, and mama with over ten years of experience working in the food industry. Read Full Bio »
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