How to Chop
The goal when chopping any vegetable is to end up with equal-size pieces. You can chop most produce lengthwise, then crosswise; onions require an additional step because of the shape.

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Food Network Magazine
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Photo By: Andrew Purcell
Photo By: Andrew Purcell
Photo By: Andrew Purcell
Photo By: Andrew Purcell
Step 1
Slice 1/2 inch off the stem end of an onion so it will sit flat, then slice the onion in half through the root. Peel both halves.
Step 2
Lay the halves flat-side down. With your knife parallel to the board, make 2 or 3 horizontal cuts; stop before the root end.
Step 3
Make even vertical cuts, stopping before the root end.
Step 4
Holding the root end and curling your fingers under, slice across the cuts you just made; the pieces will fall away.