To Spatchcock the Hens: Place the hens on a cutting board, breasts underneath, with the legs pointing down towards you. Feel for the low opening and then the upper opening. Using kitchen shears cut from the large opening up through the ribs on one side of the backbone to the upper opening. Repeat on the other side of the backbone. Repeat with the other hen. Save these two backbones for stock. Place the hens breast side up, and using the heel of your palm, gently but firmly press down on the breast bone to crack it: this will help the hens lay flat in the baking dish.
If you don't want to lay out the spatchcocked hens out flat, feel free to cut through the breast bone to create two pieces from one hen. This works great if your hens are on the larger side, as one half can easily feed one person. This means that the dish will feed four.
You can replace the hens with 8 chicken legs or thighs, skin on (about 3 lbs or 1/4 kg) Score the skin a few times