I like this technique because it gives you a lot of flexibility. You can make your onion pieces big or small. And they’ll all be pretty much the same size, which means they’ll cook at an even rate. You can use this technique on shallots, too – I find it’s sometimes easier to use a small pairing knife when chopping shallots.
An onion (or shallot)
A really sharp knife
1. Slice off the side of the onion opposite the root end.
4. Position your knife horizontally and make a series of horizontal cuts into the onion, one on top of the other, stopping just short of the root end. If you want small onion pieces, keep your cuts close to one another. If you want large onion pieces, you can space your cuts fairly widely.
5. Next make a series of vertical slices, moving from left to right across the onion half. Don’t worry if a couple of slices of onion fall off. Again, if you want small onion pieces, keep your vertical cuts close to one another. If you want larger pieces, space your cuts more widely.