How do I spatchcock a chicken and why would I?

Removing the backbone so the bird cooks flat, which halves the roasting time and fixes the dry-breast problem.

Difficulty: intermediate
Time: 15 min
Read: 3 min
Safety: caution

Short answer

Cut out the backbone with kitchen shears, turn the bird over and press the breastbone flat. It then cooks in 35 to 45 minutes instead of 90, and the breast and thighs finish at the same time instead of the breast drying while the legs catch up.

A whole chicken is an awkward shape to cook. The thighs need longer than the breast but sit lower in the oven's heat. Flattening the bird removes that problem entirely, which is why it is worth the two minutes it takes.

Safety

You are cutting through bone with a sharp tool near your other hand. Use kitchen shears rather than a knife, keep the bird flat on a board that cannot slide, and wash hands, board and shears thoroughly afterwards.

Step by step

Set the bird breast-down on a stable board.Legs towards you. A damp cloth under the board stops it moving.
Cut down one side of the backbone.Kitchen shears, starting at the tail end, cutting through the rib bones about 1cm from the spine. They are thin and cut easily — this is not brute force.
Cut down the other side and lift the backbone out.Keep it. It roasts down into an excellent stock along with the wing tips.
Turn the bird over and open it out.Breast up, legs splayed outwards.
Press firmly on the breastbone.Heel of the hand, one decisive push. You will hear it crack. That is the keel bone giving way and it is what lets the bird lie flat.
Tuck the wing tips behind the shoulders.Otherwise they burn. Or cut them off for the stock pot.
Season and, ideally, dry brine.Salt over both sides and leave uncovered in the fridge for a few hours. A flat bird has more exposed skin, so this pays off visibly.
Roast hot on a rack.200 to 220°C, 35 to 45 minutes for a 1.5kg bird. A rack lets heat get underneath, so the underside is not sitting in fat.
Check the thigh reaches 75°C.The thickest part of the thigh, away from bone. Then rest for ten minutes before carving.

Tips

Kitchen shears, not a knife. Far safer, far quicker, and they cut rib bone easily.
It is also the best way to barbecue a whole chicken — flat means even contact and even heat.
Keep the backbone and wing tips. They make better stock than the carcass alone.

Common mistakes

Trying to cut the backbone with a chef's knife — The blade skids off the bone, the bird moves, and your other hand is right there. Shears cut through poultry rib bone with no force and no slipping.
Not pressing the breastbone flat — The bird springs back into a curve and the thickest part sits proud of the tin, which recreates the uneven cooking you were trying to avoid. It needs a firm crack, not a gentle press.

If it doesn't work

Bird will not lie flat

Cause: Breastbone not cracked — Fix: Press harder on the breastbone with the heel of your hand — it should give audibly.

Skin pale on the underside

Cause: Sitting in fat — Fix: Roast on a rack over the tin so the air circulates underneath.

Wing tips burnt

Cause: Left sticking out — Fix: Tuck them behind the shoulders or remove them for stock.

Breast dry even spatchcocked

Cause: Overcooked — Fix: Check the thigh at 35 minutes — a flat bird cooks far faster than a whole one and the old timings do not apply.

Questions people ask

How much faster is a spatchcocked chicken?

Roughly half. A 1.5kg bird that takes 80 to 90 minutes whole is done in 35 to 45 minutes flat, at the same temperature.

Can the butcher do it for me?

Yes, and most will if you ask. Supermarkets also sell them ready spatchcocked, sometimes labelled as butterflied.