Spatchcocking a chicken enables you to lay it flat on a barbecue. There is less point in the procedure if you are going to cook the bird in the oven; but it's nice to introduce a bit of variety from time to time.
I usually ask my butcher to do the spatchcocking (or to joint a chicken), because I am so rubbish at it. Yesterday, I managed it myself, without serious mishap. You cut along both sides of the backbone with poultry shears or a very sharp knife, and remove it. Then you lay the chicken breast side up, and flatten it out with your hand. I marinated my chicken: I scattered over it (both sides) three cloves of garlic that I had crushed with some salt; I squeezed over the juice of a lime, added a few glugs of olive oil, grated over some more salt, and threw over a couple of sprigs of rosemary. (I would have added pepper, and perhaps chilli, had I not foreseen objections.) I left the chicken for a few hours in the roasting tin, covered with foil.
I scraped and sliced some new potatoes about 0.5cms thick, and transferred them to a bowl of cold water.
As spatchcocked chicken is designed to be grilled (at quite a fierce heat), I roasted it at a higher setting than I use for roast chicken. I pre-heated the oven to gas mark 9/240C, drained the potatoes, transferred the chicken to a plate, tipped the potatoes into the tin and stirred them with some more olive oil, put back the chicken on top, and put the tin into the oven, which I turned down to 7/220C. After 30 minutes, I turned down the oven to 4/180C, basted the chicken, and cooked it for a further 45 minutes (it was a 1.75kg bird). The risk in using this high temperature is drying out the breast; but I got away with it.
I took out the chicken, and allowed it to rest for 20 minutes on a plate sitting in the grill section above my oven. Meanwhile, I stirred the potatoes, returning them to the oven to crisp at gas mark 8/230C. (I had cooked the chicken on the middle shelf, which I moved up a level for the potatoes.)
Potatoes that have not been blanched or parboiled before roasting are inclined to stick. If you like crispy scrapings, you might consider this a bonus.
I have written this recipe in response to a request for dishes using non-battery chickens from Kate on A Merrier World. My chicken was a Label Anglais, about which you can read more information here.