How to Slice Onions

Onion Half Sliced
Onion Half & Sliced Onion. DK/Getty Images
  • 01 of 06

    Start With Firm, Smooth-Skinned Onions

    Onions
    Bowl of Onions. Molly Watson

    The better the onions, the better the slices.

    Start with onions that have smooth skins, feel heavy for their size, and are supremely firm.

    "Freshness" isn't so much the issue, since onions are excellent storage vegetables, as is looking for onions that have been stored properly, after having been "cured" or lightly dried before being stored in a cool, dark place. 

    One note if you're working with more than one onion: do as the pros do and do each step with each onion before...MORE moving on to the next step. Amazingly, it really does save time.

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  • 02 of 06

    Cut Off the Stem End

    Trimming an Onion
    Cut Off Stem End of Onion. Molly Watson

    The other key to perfectly sliced onions is to use a very sharp knife. Some people will worry that a sharp knife is dangerous, but a sharp knife is actually safer—it will cut where you want it to cut instead of slipping off the surface and cutting something else (like your finger!).

    So, using a very sharp knife, cut off and discard stem end, being careful to hold the onion steady as you do so.

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  • 03 of 06

    Halve the Onion

    Cutting Onion in Half
    Halving Onion. Molly Watson

    Set the onion on a work surface on the flat cut end to keep it steady and cut it in half lengthwise (down through the root end), using the intact root end to hold each half together.

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  • 04 of 06

    Remove the Onion Skin

    Peeling an Onion
    Onion Peel. Molly Watson

    Peel the onion, removing any and all of the papery skin and even the external layer of onion if need be to get all of the skin off.

    If you tear up from onions easily or the onion at hand has a particularly clingy peel, you can do this under running water. The water will wash away the sulfur that causes the tears and get between the onion and the peel, making the latter easier to remove.

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  • 05 of 06

    Slice the Onion

    Slicing an Onion
    Onion Slicing. Molly Watson

    On the work surface, lay the onion on its large flat side, hold it carefully by the still-intact root end, and use a very sharp knife to slice the onion as thick or as thin as you like.

    Push the onion slices aside and repeat with the second half. 

    I like to keep the tip of the knife down, lifting and pressing down the knife handle in almost a rocking motion rather than hacking away lifting the entire knife up and down, but both methods have their fans.

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  • 06 of 06

    Voilà! Sliced Onions

    Pile of Onion Slices
    Onion Slices. Molly Watson

    You will now have a nice pile of onion slices. What to do with them?

    Use sliced onions to make caramelized onions, French onion soup, or your favorite onion-y recipe.

    They're also good on pizzas, added to salads, or offered for people to add to burgers.