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Let me show you how to cut an onion like a pro!! Less tears, beautiful uniform onion slices and/or dices in matter of minutes. If you get tears, it’ll be tears of joy! 😉
With this method, you’ll learn how to slice and dice your onions. And if you haven’t already, check out my Onion 101 guide to learn when to use what onion and other tips.
HOW TO CUT A ONION:
Learning how to cut onion is a skill worth investing time in as this wonderful ingredients adds so much flavor to many, many dishes.
As a home cook, we’re not under pressure to rush, so take your time and practice with safety in mind.
Step 1. Cut the onion in half
- Start off by cutting the onion in half with peels and all.
- Peel off the outer layers from both halves and discard.
- Give both halves a quick rinse with water, if needed.
TIP: A good sharp knife makes a world of difference. A dull knife bruises the onion flesh, which makes the flavor more pungent AND makes you cry easily.
Step 2. Trim off the top end
- The next step is to trim off the top end. Leave the root end intact as it holds all the layers in place, making it easier to cut.
Step 3. Slice
- Place the onion half flat-side down and root end to your left (or on your right, if you’re left-handed).
- Hold the bottom portion of the onion with your left hand and hold your knife perpendicularly to your body.
- Starting from the top, slice the onion vertically as close to the root end as possible but without cutting through the root. (Note: Move your knife down and back, instead of up and down.) If you need thin onion slices or small dices, cut it closer. If you need thicker slices, or bigger dices, cut wide strips.
- Continue slicing until you reach bottom of the onion.
- Now, if you need onion slices, then simply cut the root end off. If you need diced onion, skip this step and continue with the next step.
TIP: Onion slices cut from pole to pole, as described above, hold their shape well during cooking.
Step 4. Dice the onion
- Keep the root end on your left and then slice across the cuts. Cut it vertically toward the root end and now you have perfect diced onions. (Note: I don’t make any horizontal cuts before dicing, as I don’t find it necessary.)
TIP: If your dish requires a strong onion flavor, mince the onion in a food processor.
Here are a few FAQ’s:
Which side of the onion do you cut and what helps you not to cry?
- So, cut on the top side with the step by step method. Always leave the root intact, this stops your eyes from tearing up and helps to keep the slices in place, making it easy to manage.
- There are many methods of cutting an onion without crying ranging from placing it in the fridge, rubbing onion on your knife prior to cutting, freezing the onion and some even suggest microwaving it. Fun fact: I wear contacts and slicing onions never tears me up!!!
How do you slice onions for caramelizing?
- For caramelized onions, you need slices. Follow steps 1-3 above and you’ll get perfect slices.
How do you store excess raw onions?
- You can store raw sliced onions without the fridge smelling like them! Place them into a ziplock bag and store them for 7-10 days in the fridge, or freeze for up to 1 month.
How do you clean your cutting surface and get the onion smell out?
- Cut a lemon in half and then scrub away with the cut side down on your wooden board. Then rinse with warm water and dry your board.
- If the above method didn’t work for you, then add salt. This will neutralize the odor.
- Do not let the smell linger on your board as it will intensify and go into other food you slice on the board.