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How to Break Down an Onion 12:24

Patricio Sandoval

Learn the fundamental techniques of handling and dicing an onion.

How to Break Down an Onion 12:24

Patricio Sandoval

Learn the fundamental techniques of handling and dicing an onion.

Prep Time Cook Time Total Time Serving Size

The Steps

  1. 1. Place the yellow onion on the cutting board, root-side up. Holding the onion firmly with the non-dominant hand (fingers tucked under), use a sharp chef’s knife to cut the onion in half, through the root down to the stem. Repeat with the red onion. 01:17

  2. 2. The culinary school method of cutting an onion: Place an onion half flat-side down on the cutting board. Trim off the stem end; discard. Peel off the skin, and remove the first layer of onion. Wipe the knife and clean off the board. 03:35

  3. 3. Place the onion flat-side down, cut side pointing in the direction of the knife hand. Place the palm of your non-dominant hand on top of the onion, fingers out of the way. Holding the knife parallel to the cutting board, slice through a bottom layer of the onion, stopping about 1/2 inch before the root. Repeat this process, cutting a new layer above the previous with a similar thickness, as many times as needed. Stop when you reach the top. 04:26

  4. 4. Turn the onion 90 degrees so the root end points away from you. Start on one rounded side of the onion and cut through to about 1/2 inch from the stem. The first cut may separate completely from the onion since it is not attached to the root. This is okay. Continue making cuts the same distance apart across the onion until you reach the other side. Hold the onion together with the non-dominant hand so it doesn't fall apart. 05:31

  5. 5. Turn the onion 90 degrees back to the first position. This time, with the knife perpendicular to the board, cut the onion in a downward motion. The pieces should fall in a diced shape. Continue to make even slices down the onion towards the root. You will end up mostly with diced onion, though some pieces may be uneven. 06:06

  6. 6. Patricio's favorite way to cut an onion: Cut an onion in half from root to stem. Place an onion half flat-side down on a clean cutting board. Trim off the root and stem ends then peel off the skin and first layer of onion. 06:59

  7. 7. Using the tip of a sharp knife, cut even slices along the onion in a direction parallel to the cut end until you reach the other side. Stack the slices back together into an onion shape. Repeat with the other half, as needed. 08:55

  8. 8. Remove three adjacent slices from the "deck" of onion. Lay them flat on the board. Remove the center pieces until you're left with a half moon of rings. Make cuts of equal width along the onion; this produces a precise dice. Repeat as needed. 10:05

What You'll Need

Any variety of onion including yellow, red, white, or Spanish.

Chef Notes

Learning to cut an onion is crucial because onions are fundamental to many dishes. Onions can be difficult to cut because they are round and inherently unstable. For safety purposes, be sure to cut a flat side onto the onion so there is always a stable base to place on the cutting board. Make sure the board and knife are not slippery and always keep the fingertips tucked under in a claw shape to prevent cuts.

In this tutorial, Chef Patricio demonstrates his mother's method of cutting an onion. Be advised that, for safety reasons, this method is not recommended since the knife cuts downward towards the hand.

Onions and tears: When onions are cut, they release a sulfuric compound that reacts with the moisture in the eyes to produce a form of acid. This acid burns the eyes, causing more tears. To reduce tears during onion cutting, be sure to use a sharp knife so less of the compound is released. Other methods that work for some include refrigerating the onion, cutting the onion under water, and wearing goggles and/or contacts.


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Chef Patricio Sandoval


Chef Patricio Sandoval became a culinary star in Chicago by delivering refined Mexican street food with bold flavors at his r... read more