Prep Cook how-to

How to Dice an Onion

Onions are prepped in nearly every kitchen.

Updated By the Career Education Institute Curriculum Team
Quick answer

Onions are prepped in nearly every kitchen. In short: cut; halve; make, then complete the remaining steps below.

Step by step

  1. Cut off the top and peel.

  2. Halve through the root.

  3. Make horizontal cuts toward the root without cutting through.

  4. Make vertical cuts toward the root.

  5. Slice across to create dice.

  6. Discard the root end.

Safety reminders for prep cooks

  • Use cut-resistant gloves with slicers
  • Keep knives sharp and stored safely
  • Lift with your legs
  • Keep raw and ready-to-eat foods separate

Prep list · Dice · Julienne · Brunoise · Chiffonade · Portion: see the full prep cook glossary.

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