Keep this shape and go to your cutting board. Rest the tips of your fingers on top of whatever you're about to cut. Your fingertips should be perpendicular to the surface of the food, with your fingernails acting like a shield.Your thumb should be perpendicular to the food as well, but on the side. The thumb also helps keep the food stable while you're cutting. Here's a shot of the thumb position: With your fingers in this position, you run much less risk of a serious injury than if you were holding the food with the pads of your fingers. If the knife slips while you're in this position, it will only hit against your hard fingernails. Even if it does knick the skin, the injury will be far less severe.
Depending on the size of the food is that you're trying to cut, you can rest your wrist on the cutting board. This adds some extra stability and control.
This position can feel a little cramped and unnatural at first. Spend a few evenings actively using this technique and you'll get the hang of it. It also helps if you happen to have a chef on hand to shout at you every time you forget, we happen to know...
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(Images: Emma Christensen for the Kitchn)