Chopping means simply cutting something into small, usually even, pieces. You need to chop vegetables, most often onions and garlic, for many different cooking techniques, including sautéing. Chopping a vegetable follows a pretty simple procedure. This example shows how to chop an onion.
Cut the vegetable in half.
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If you’re chopping an onion, you also need to peel back the papery skin and cut off the top, leaving the root end intact.
Place each half cut-side down and slice the vegetable lengthwise in parallel cuts.
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Leave 1/8 to 1/4 inch between the slices.
Make several horizontal cuts parallel to the board.
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You can decide how thick you want these cuts to be.
Cut through the vegetable at right angles to the board.
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Make the pieces you cut as thick as desired. If you’re working with an onion, just discard the root end when you’ve chopped the rest of the onion half.