How to dice an onion by slicing toward the root, then cross-cutting
Make lengthwise slices toward the root (keeping the root intact), then cut across those slices to create an even dice.
With the onion half flat-side down, slice into the root end all the way around to set the dice size. Then hold the onion together and cut across the slices to produce diced pieces, removing the root at the end.
The short version
- Slice width sets dice size
- Keep pieces together for control
- Use a slicing motion when rocking isn’t practical
What you need
- chef's knife
- cutting board
How to do it
- 1
Peel the onion half and place it flat-side down.
Watch this step - 2
Slice into the root end all the way around, making the slice width equal to your desired dice size.
Keep the root intact to hold the onion together.
Watch this step - 3
Hold the onion together with fingers tucked back, then cut across the slices to dice.
Use a slicing motion rather than trying to rock if the onion is large.
Watch this step - 4
Cut off and discard the root end after dicing.
Watch this step
What goes wrong
Inconsistent slice widths leading to uneven dice
Match each cut to the size you want the final dice to be
Trying to rock-chop a large onion awkwardly
Use a forward slicing motion using the knife’s curve
Why it works
The first set of slices defines uniform piece size; the intact root keeps layers aligned for cleaner, safer cross-cuts.
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