How do I chop an onion properly?

The standard onion dice looks like a trick and is really just using the root as a clamp. Leaving it intact until the last cut means the layers stay together and every piece comes off the same size.

What you'll need

• Sharp chef's knife
• Chopping board
• Damp cloth under the board (optional)

Step by step

1. Put a damp cloth under the board so it cannot slide.A sliding board is the most common cause of kitchen knife injuries.
2. Cut the onion in half from top to root.Through the root, not across it. The root end is the hairy one.
3. Peel each half, leaving the root intact.The root is what holds everything together. Do not trim it off yet.
4. Lay a half flat and make two or three horizontal cuts towards the root, stopping short of it.Keep the knife parallel to the board. Fingers on top, well clear of the blade.
5. Make vertical cuts from top to root, again stopping short of the root.The spacing here sets the dice size.
6. Slice across the cuts to release the dice.Each slice releases a row of evenly sized pieces.
7. Discard the root once you reach it.The last centimetre or so, which held everything together.
8. For rings or slices instead, cut across the whole onion after peeling.Different cut for a different purpose — rings for frying, dice for a base.

Tips

• A sharp knife genuinely reduces crying, because it ruptures fewer cells and releases less of the compound that irritates your eyes.
• Chilling the onion for fifteen minutes first also reduces the effect noticeably.
• The root has the highest concentration of the irritant compounds, which is another reason to leave it intact until last.

Common mistakes

• Cutting the root off first — The layers fall apart and every cut becomes fiddly and uneven.
• Using a blunt knife — It crushes rather than cuts, which releases more irritant and makes you cry more.
• Cutting all the way through to the root — The half falls apart and you lose the clamp that makes the method work.

Questions people ask