Dice an Onion

Trim, peel, halve, and cut the onion in a controlled pattern to make small, even pieces.

Easy · 5-10 minutes

Tools

  • Sharp chef's knife or paring knife
  • Cutting board

Materials

  • Onion

Safety

  • Use a sharp knife; dull knives slip more easily.
  • Keep the cutting board stable and dry while cutting.
  • Curl your fingertips under and keep them away from the blade.
  • Cut slowly and stop if the onion or board shifts.
  • Clean the knife and board after use.

Steps

  1. Step 1: Prepare the onion and workspace

    • Wash the onion if needed to remove dirt from the outside.
    • Place a cutting board on a stable surface.
    • Set out a sharp knife.

    Check: The board is not sliding. · The onion is clean and dry enough to hold securely.

  2. Step 2: Trim the ends

    • Cut off the stem end of the onion.
    • Cut off the root end, or trim only a small amount if you want the layers to stay together more easily.

    Check: Both ends are flat. · You have a stable surface for the next cut.

  3. Step 3: Peel and halve the onion

    • Stand the onion on a flat end and cut it in half from top to bottom.
    • Remove the papery skin and any tough outer layer from each half.

    Check: Both halves are peeled. · Each half sits flat-side down securely on the board.

  4. Step 4: Make lengthwise cuts

    • Place one onion half flat-side down.
    • Make several vertical cuts from top toward the root end, spacing them to match the size of dice you want.
    • Do not cut all the way through the root end if you left it attached.

    Check: The cuts are mostly even. · The onion half is still holding together.

  5. Step 5: Make horizontal cuts

    • Hold the onion half steady.
    • Carefully make 1 to 3 horizontal cuts parallel to the board, depending on the onion size and desired dice.

    Check: The knife is moving parallel to the board in a controlled way. · The onion is still intact enough to slice cleanly.

  6. Step 6: Cross-cut to dice

    • Slice across the onion from front to back.
    • As you cut, small diced pieces will fall away.
    • Stop when you reach the root end and discard it.

    Check: The pieces are close to your desired size. · No large uncut sections remain.

  7. Step 7: Repeat and clean up

    • Repeat the same cuts with the second onion half.
    • Gather the diced onion for cooking or storage.
    • Clean the knife and cutting board.

    Check: Both halves are diced. · The work area is clean and safe.

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Dice an Onion0 of 7 steps done

Written by AI, not checked by a tradesperson. How this works

Step-by-Step Instructions

Step 1 of 7

Prepare the onion and workspace

Diagram for step 1: Prepare the onion and workspace
Fig. 1Prepare the onion and workspace
  • Wash the onion if needed to remove dirt from the outside.
  • Place a cutting board on a stable surface.
  • Set out a sharp knife.
Check

The board is not sliding. • The onion is clean and dry enough to hold securely.

Was this step clear?
Step 2 of 7

Trim the ends

Diagram for step 2: Trim the ends
Fig. 2Trim the ends
  • Cut off the stem end of the onion.
  • Cut off the root end, or trim only a small amount if you want the layers to stay together more easily.
Check

Both ends are flat. • You have a stable surface for the next cut.

Was this step clear?
Step 3 of 7

Peel and halve the onion

Diagram for step 3: Peel and halve the onion
Fig. 3Peel and halve the onion
  • Stand the onion on a flat end and cut it in half from top to bottom.
  • Remove the papery skin and any tough outer layer from each half.
Check

Both halves are peeled. • Each half sits flat-side down securely on the board.

Was this step clear?
Step 4 of 7

Make lengthwise cuts

Diagram for step 4: Make lengthwise cuts
Fig. 4Make lengthwise cuts
  • Place one onion half flat-side down.
  • Make several vertical cuts from top toward the root end, spacing them to match the size of dice you want.
  • Do not cut all the way through the root end if you left it attached.
Check

The cuts are mostly even. • The onion half is still holding together.

Was this step clear?
Step 5 of 7

Make horizontal cuts

Diagram for step 5: Make horizontal cuts
Fig. 5Make horizontal cuts
  • Hold the onion half steady.
  • Carefully make 1 to 3 horizontal cuts parallel to the board, depending on the onion size and desired dice.
Check

The knife is moving parallel to the board in a controlled way. • The onion is still intact enough to slice cleanly.

Was this step clear?
Step 6 of 7

Cross-cut to dice

Diagram for step 6: Cross-cut to dice
Fig. 6Cross-cut to dice
  • Slice across the onion from front to back.
  • As you cut, small diced pieces will fall away.
  • Stop when you reach the root end and discard it.
Check

The pieces are close to your desired size. • No large uncut sections remain.

Was this step clear?
Step 7 of 7

Repeat and clean up

Diagram for step 7: Repeat and clean up
Fig. 7Repeat and clean up
  • Repeat the same cuts with the second onion half.
  • Gather the diced onion for cooking or storage.
  • Clean the knife and cutting board.
Check

Both halves are diced. • The work area is clean and safe.

Was this step clear?

Common Mistakes

  • ×Using a dull knife, which can slip and crush the onion.
  • ×Letting the cutting board slide during cutting.
  • ×Cutting with the rounded side of the onion down instead of the flat side.
  • ×Making uneven cuts, which leads to uneven cooking.
  • ×Cutting off too much of the root too early, causing the onion layers to fall apart.

When to Call a Professional

  • This task does not normally require a professional.
  • Ask for help if you are not comfortable using a knife safely or have limited hand control.

Notes

  • Leave the root end attached until the final cuts if you want neater dice.
  • For smaller dice, make closer vertical and cross-cuts.
  • Chilling the onion briefly or using good ventilation may reduce tearing.

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