Knife skills and safety
How to hold a knife, how to keep your fingers out of its way, how to cut an onion, and how to keep a board safe around raw meat. After this you can prep faster and with far less risk.
THE FIRST RULE
A sharp knife is the safe one
A sharp blade bites into the food where you put it and needs almost no push. A blunt one slides off a tomato skin or an onion's curved side, and because you're pressing harder, it slides with force behind it, straight towards your other hand. Most kitchen cuts come from blunt knives, not sharp ones.
Test it on a tomato. A sharp knife starts cutting under the weight of the blade. If you have to saw at the skin, the knife needs sharpening, and until then you should cut slowly and with the tomato held firmly.
Check yourself
A sharp knife is safer than a blunt one, even in the hands of someone who has never cooked.
Show the answer
True
True, though it sounds backwards. A blunt blade slips off skins and curved surfaces, and it slips while you are pushing hard, so it arrives at your hand with force. A sharp knife goes where you put it and needs very little pressure. Keep knives sharp and keep your fingers curled.
The grip and the claw
- Pinch the blade, don't grab the handle
Thumb on one side of the blade and the side of your index finger on the other, just in front of the handle. The other three fingers wrap the handle. It feels odd for a day and then it feels like control.
- Curl the other hand into a claw
Fingertips tucked under, knuckles forward. The flat side of the blade rests against your knuckles, so the edge physically cannot reach your fingertips.
- Let the knuckles steer
Your knuckles are the guide rail. Move that hand back a few millimetres at a time and the slices come out the same thickness without you measuring anything.
- Move the food, not your arm
Keep the tip of the knife near the board and use a forward-and-down slicing motion rather than chopping straight down. You're slicing, not hacking.
Check yourself
Reza is slicing carrots. He holds them with his fingers flat and stretched out along the board, tips forward, and lifts the knife high between cuts. What is the single most important change?
- Hold the knife further back on the handle, so his hand stays as far from the edge as possible
- Cut faster so there is less time to slip
- Curl his fingertips under so his knuckles, not his nails, are nearest the blade
- Use a bigger knife
Show the answer
Curl his fingertips under so his knuckles, not his nails, are nearest the blade
Right. With the claw, the flat of the blade rides against your knuckles and the edge simply can't reach your fingertips. Flat, stretched-out fingers put the tips in the line of the blade.
The cuts, and why size is not decoration
- Slice: flat pieces of even thickness. Onions for a stew, aubergine for the oven.
- Dice: cubes. Small dice for a sauce that should be smooth-ish, larger for a stew where you want to see the pieces.
- Mince: chopped very fine, almost a paste. Garlic, ginger, chillies, things you want spread evenly and gone.
- Even size matters more than pretty size. Pieces that differ cook at different speeds, so you get some raw and some mushy in the same pan.
- Bigger pieces for longer cooking. Something that will simmer for two hours should be cut much larger than something that gets eight minutes in a pan.
Check yourself
Match each job to the cut that suits it
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- Garlic for a quick pan sauce → Minced very fine
- Potatoes for a two-hour stew → Large chunks
- Onion for a smooth tomato sauce → Small dice
- Aubergine to roast in the oven → Even slices
An onion, start to finish
- Cut off the top, keep the root
Slice off the stem end. Leave the hairy root end on: it's what holds all the layers together while you work.
- Halve it through the root
Stand the onion on its cut top and slice down through the root, so each half still has half a root. Now peel. The skin comes away far more easily than on a whole onion.
- Put it flat side down
This is the safety step. A flat face on the board means the onion cannot roll, so nothing rocks under the blade.
- Lengthways cuts towards the root
With the root away from you, make a row of cuts down the length, stopping just short of the root so the half stays in one piece. Closer cuts give a finer dice.
- Then cut across
Claw hand on top, slice across the cuts you just made and the dice falls away by itself. When you reach the root, put it in the bin, don't chase the last centimetre with your fingers close to the blade.
Check yourself
Elham cuts the root off her onion first, peels it whole, then tries to dice it. The layers slide apart all over the board and the pieces come out every size. What should she change?
- Use a serrated knife for onions
- Cut the top off, halve it through the root, and leave the root on
- Freeze the onion for ten minutes first
- Dice it under running water, which holds the layers together and stops the stinging
Show the answer
Cut the top off, halve it through the root, and leave the root on
Yes. The root is the hinge that holds the layers. Keep it on, work from the other end, and the onion stays in one piece until you're finished.
Check yourself
Safe habit or risky habit?
- Rinsing raw chicken under the tap before cooking
- A damp cloth under the cutting board
- Chopping salad on the board you just boned chicken on, without washing it
- Cutting all the vegetables first, then the meat, then washing everything
- Grabbing at a knife as it slides off the counter
- Laying a halved onion flat side down before slicing
Show the answer
Safe: A damp cloth under the cutting board, Cutting all the vegetables first, then the meat, then washing everything, Laying a halved onion flat side down before slicing
Risky: Rinsing raw chicken under the tap before cooking, Chopping salad on the board you just boned chicken on, without washing it, Grabbing at a knife as it slides off the counter
Keeping the knife in shape
- Wash it by hand and dry it straight away. Dishwashers batter the edge and loosen handles.
- Never leave it in the sink, especially under water. That's how people cut themselves reaching for a sponge.
- Cut on wood or plastic. Glass, stone and metal boards blunt an edge in weeks.
- A honing steel is not a sharpener. It straightens an edge that has bent over; when the blade is genuinely dull it needs a whetstone or a sharpening service.
Lesson recap
- Sharp knives are the safe ones, and a board that can't slide matters as much as the blade.
- Pinch the blade with thumb and index finger, and curl the other hand into a claw so the knife rides on your knuckles.
- Cut evenly, and size the pieces for the cooking time: big for long stews, small for quick pans.
- Keep the onion's root on until the end, and never let raw meat, or a board that touched it, meet food that won't be cooked. Don't wash raw chicken.