I learned spatchcocked chicken from a book, and it took me a while (and a few nicked fingers) to perfect the technique. The New York Times article recommends pressing down on the centre of the breast to flatten the bird, but this method is unreliable for two reasons.

First, the flattening manoeuvre is designed to break or dislocate one or both of the clavicles at the sternum, and this always happens at the weakest point -- which may not be at the sternum, where you want the break to be. Second, most fryer chickens (the best size for spatchcocking) are so young that their joints are very flexible, so pressing might not achieve the aim at all.

So the better method is to take your stiff, very sharp knife (the one you used to cut the ribs away from the backbone) and cut the cartilage that covers the point where the clavicles join the sternum. (Note that shears won't do this job.) Then turn the bird over and press it flat, with your knuckles or the heel of your hand on that joint. The result will be a firm snap, at the sternum.

Steve, I would love to try your puttanesca recipe, but I would have to do it with somebody else's husband. Mine won't touch it -- or arrabiata, either. One of his few flaws is a prejudice against hot peppers.