Sue Torres's Chef's Secret: Dicing an Onion
Using a sharp knife, slice onion in half lengthwise, through the root. Cut a bit off the top of each half; pull away papery skin and tough outer layer, and discard. Place halves, cut side down, on cutting board. Slice onion lengthwise, at even intervals, up to but not through the root end. Slice across onion horizontally, at even intervals, up to but not through the root end. Holding root end, cut onion crosswise at even intervals. The pieces will fall as you chop.