There are many ways to skin a cat; there is only one way to dice an onion. The first sign that you are not dicing your onion properly is that it's rolling around on the cutting board. An onion is a globe; to transform this into an orderly mound of miniature dice, risk-free, you need a plan of attack.

When we asked some of our non-cook friends to dice onions, we found that not only does it seem that everybody has their own method—but that the results were terrifying:

So many things are wrong with these photos—the paring knife! The onions standing upright on their rounded base! Forget that the slices are jagged and uneven; these onions are terribly unstable.

For the safest, most geometrically sound, onion dicing method, we look as always to our resident knife expert Matt Card. His strategy considers the onion from every angle, first stabilizing the base, then breaking it down into shapes optimal for extracting cubes. The result is a sparkling mound of perfect dice, produced at assembly line-speed.

Sharpen your Kiji, stabilize your cutting board, then follow Matt Card’s guide to dicing an onion.

  1. Slice off the top stem end of the onion, where the skins meet and form a point or a ponytail shape.
  2. Flip the onion over, orienting the root end to the North Pole. You want to keep the root end intact; this holds the onion together while dicing.
  3. Cut downward through the center of the onion.
  4. Flip one half of the onion over, flat side down. Starting near the center of the onion, make a shallow incision in the skin, perpendicular to the top of the onion.
  5. Pull the papery skin back from the incision, in two flaps, and pull it off from the bottom of the onion.
  6. Place the onion half flat side down. Hold the onion with your hand formed into a claw shape, knuckles forward and fingertips rolled slightly back and angled in for protection. This is the claw grip: do this always to keep your fingertips safe.
  7. Slice lengthwise, in tight, even parallel cuts, perpendicular to the root end. Do not cut all the way through the root; again, this keeps your onion intact.
  8. When you reach the center of the onion, chop straight through the middle and through the root end, in order to split the onion in half.
  9. Flip the remaining onion half over.
  10. Repeat step 7, cutting long parallel strips through the onion without slicing through the root end.
  11. Turn your onion 90 degrees, horizontally, and slice once more.

Congratulations! You have now diced an onion.

Watch Matt perform his technique on Instagram.

For more knife knowledge, read up on why your cutting board is killing your knives; why you need a carrot strategy; learn how to break down a pineapple; and how to reduce scallions into fine, feathery ribbons.

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