Knife basics: hold a knife and dice an onion

Why this comes first

Almost every recipe starts with cutting something. When the pieces are the same size they cook at the same rate, so a pan of onions softens together, with no burnt bits next to raw ones. Good knife work also makes cooking calmer. Once you can dice an onion in a couple of minutes, a recipe that starts with “1 onion, diced” stops feeling like a chore.

You need a chef’s knife with a blade about 8 inches long and a large cutting board. Keep the knife sharp. A dull blade skids off an onion’s skin and has to be forced, and that force is what sends a knife into a finger.

Set up the board

Put a damp paper towel or a thin, damp dish towel under the board, then press on its corners. If it slides or rocks, fix that before you cut anything, because a board that moves makes the knife slip.

Hold the knife: the pinch grip

Most beginners wrap every finger around the handle, the way you’d hold a hammer, and that lets the blade wobble. The pinch grip holds it steady.

1. Wrap your middle, ring and little fingers around the handle, close to where it meets the blade.
2. Pinch the flat of the blade just in front of the handle, with your thumb on one side and the bent side of your index finger on the other.
3. Keep your wrist straight, so the blade lines up with your forearm.

It feels odd for the first few days. You have it right when the blade doesn’t wobble as you cut and your hand stays relaxed. If your knuckles are white, you’re gripping too hard.

Protect your other hand: the claw

Your other hand holds the food, and it is the hand that gets cut. Curl its fingertips under, so you hold the food with your fingertips and your middle knuckles stand forward, closest to the blade. Tuck your thumb behind your fingers. As you cut, the flat side of the blade rests lightly against those knuckles. With your fingertips behind them, the edge has nothing to catch.

To make the next cut, slide the claw back a little and let the knife follow. Your knuckles set the thickness of each slice: move back a quarter of an inch and you get quarter-inch slices. Go slowly. Speed comes by itself after a few weeks, and it’s worth nothing until the cuts are even.

The cutting motion

Rest the tip of the knife on the board and push the blade forward and down through the food, so it slices as it goes. Lift the back of the blade, move along, and push again. Chopping straight down like a guillotine crushes soft food such as tomatoes and onions and tires your arm. Listen as you go: a sharp knife through a firm vegetable makes a soft, even tap on the board, and a loud crunch followed by a slide means the blade is dull or the food is rolling.

Dice an onion

The root end, the hairy end, holds the layers of an onion together. Leave it on until the very last cut.

1. Cut about half an inch off the stem end, the pointed top. Leave the root end alone.
2. Stand the onion on the flat end you just made and cut it in half from top to bottom, straight through the root.
3. Peel off the papery skin, and the first layer too if it is tough or dry. Lay both halves flat side down.
4. With the root end pointing away from your knife hand, make lengthwise cuts about a quarter of an inch apart, stopping each one just short of the root so the slices stay joined.
5. Now cut across those slices, starting at the cut end and working toward the root, with your hand in the claw. The onion falls away in small, even squares.
6. Stop when you reach the root. Throw the root end away, or save it for stock.

Closer cuts give a finer dice. If your eyes sting, a sharper knife helps, since it crushes fewer of the onion’s cells, and a cold onion from the fridge stings less too.

Peel and mince garlic

1. Break one clove off the head. Lay it on the board, put the flat of your knife on top with the edge facing away from you, and press down with the heel of your hand until you feel the clove give.
2. The skin now slips off. Cut away the hard brown tip where the clove was attached to the head.
3. Slice the clove thinly. Gather the slices into a pile and chop across them, rocking the blade with your other hand flat on the top of the blade near the tip.
4. Scrape the pile together and chop again until the pieces are about the size of a grain of rice, or smaller if the recipe says “finely minced.”

Chop herbs

Soft herbs such as parsley, cilantro, basil and dill bruise easily and turn dark and wet on the board. Dry them well after washing, because wet leaves clump. Pick the leaves off thick stems, gather them into a tight pile and slice through it once, then turn the pile and slice across. Two or three passes are enough; more than that mashes them.

Keep it clean and safe

• Cut vegetables and herbs before raw meat, poultry or fish, or keep a separate board for raw meat. After raw meat, wash the board, the knife and your hands with hot, soapy water before they touch anything else.
• Never try to catch a falling knife. Step back and let it land.
• Don’t leave a knife in a sink full of soapy water, where someone can reach in and find it with their hand.

Common mistakes

How to tell it’s right

Spread a handful of your diced onion on the board and look. Most pieces should be close to the same size, more like squares than strips, with no long stringy bits from near the root. Minced garlic should be a fine, moist pile with no whole slices left in it. Chopped parsley should be bright green and feel almost dry when you pick some up, with no dark juice on the board. Your claw hand should have stayed relaxed, and the edge should never have touched your skin.