Slice the onion in half vertically through the stem and root ends.
Place the two halves cut side down on the chopping board and slice away about ½-inch of the stem end.
At this point, the peel should come away easily. If it doesn’t, you can either gently warm it against a hot pan for a short while to loosen the skin OR peel away the entire first layer of the onion, too (which is often tougher than the rest of the onion anyway).To peel a whole onion, slice the stem end, then use the tip of the knife to carefully cut through the peel layer down both sides of the onion, making it easier to slide the knife under the peel and remove it.Note: how to peel pearl onion is described in the blog post.
How to Cut Onion Rings
Slice off the stem end of the onion and peel away the papery skin.
Use one hand to hold the onion steady and the other to carefully slice the onion rings to your desired thickness with a sharp knife.To help steady the onion, optionally slice a tiny slither of onion from one side of the onion to lay on your chopping board.
Once you've cut more than half the onion, it's easier to change your grip, using your thumb and finger to hold together the sides of the onion, cutting between them.
How to Slice an Onion
There are two ways to slice an onion - pole to pole (think north and south pole on a globe), meaning root to stem, OR orbitally (aka crosswise). The former produces sweeter onion and ruptures fewer cell walls for less chance of tears. The latter is slightly easier to cut, though.
Pole-to-Pole SlicesChop the onion in half through the stem/root ends, cut away the stem end from each half (about ½-inch should do it), and peel away the skin. The intact root end will help hold the onion together while you cut.With the onion halves cut side down, use your non-dominant hand to hold it in place while using your other hand to make parallel slices in the onion to your desired thickness. Repeat with the remaining onion half.Orbital SlicesCut the onion in half and then slice off the root and stem end.Use your non-dominant hand to hold the onion while cutting slices from root to stem.Alternatively, halve and peel the onions, then use a mandoline for perfectly even sliced onion (or onion rings).
Traditional Diced Onion
Halve and peel the onion/s, slicing off the stem end.
Place both onion halves cut side down on your chopping board. Then, working one at a time, use your sharp knife to make parallel slices across the onion from the cut stem end up to -but not through- the root end.
Use your knife to slice horizontally from the stem end to the root 2-3 times.
Holding the onion firmly (keep the grip tight) with your non-dominant hand, use the other to slice across the onion, perpendicular to the first slices. When it gets tricky to slice, flip the onion forwards and continue to cut close to the root.How thick/thin you make the slices through the top of the onion will determine how fine the diced onion pieces are. Roughly ¼ inch = small dice/ finely chopped onion, 1/2=-inch = medium dice, and ¾-inch is a large dice.
Angled Method Diced Onion
Halve and peel the onion/s, slicing off the stem end.
When placing the onion halves on the chopping board, turn the onion so the root and stem ends are to the side and slice across the onion, but not all the way, as thick as you’d like.
Flip the onion around, so the root and stem are on top and bottom rather than side to side. Use your knife to follow the natural grain of the onion. At the halfway point, flip the cut edge onto the board and continue to slice the rest of the onion. Finish off the top bit where you hadn’t cut through the onion entirely.Alternatively, use a "food chopper" tool. It usually comes with a thicker and thinner grid pattern. Just slice the onions in half, peel them, and cut away both ends first. Then press them through the chopper.
How to Mince Onion
Follow the method for diced onion, making the slices in the onion very close together.
After cutting, if the pieces are still too big, rock your knife back and forth (using your fingers over the top of the knife to help anchor it in place) over the onion to your desired consistency.Alternatively, use a mini food processor for ‘instant’ minced onions.
How to Grate an Onion
For this method, you'll need a box grater. You can peel the onion from whole or halved (after chopping off the stem end and removing the peel).
Rather than standing the box grater upright, turn it on its side and place it over a dish or tray (to catch the shredded onion).
Holding the box grater to the lower dish/tray, you can use your body weight to push the onion over the wider side of the grater and grate it.Alternatively, use a grating disk in a food processor to get it done quickly and with minimal effort (though the cleanup is a little more annoying).
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Notes
What knife is best? The best knife to cut onion is a very sharp one! An 8-10 inch sharp chef's knife, santoku knife, or a thin cleaver knife will work best. Avoid serrated and/or blunt blades.How to cut onions without crying? The more you slice/chop an onion, the more tear-producing gases will release into the air. So chopping the onion quickly and minimally is key. When dicing/mincing, you can either freeze the peeled onion for 15 minutes or soak it in cold water for 15 minutes. Wearing airtight/swimming goggles can also help.How to store fresh onions (whole and cut)?Whole onions: Whole onions prefer a cool, dry, dark, and well-ventilated spot, like in your pantry in a fruit basket or even placed within stockings with a knot between each one. This way, they can store for between 2-3 months.Peeled/cut onions: Once cut, store onions in a non-porous airtight container (like glass) in the refrigerator and use them within 5-7 days. They’re best within 3-4 days as the flavor becomes harsher over time.How to freeze onions? You can freeze raw sliced/diced/minced onion in the freezer for up to 3 months in an airtight Ziplock bag or in smaller portions wrapped in plastic wrap. Use them from frozen or thaw them first.Check the blog post for more information about different types of onions, uses for each type of chopped onion, and answers to top FAQs!