Spatchcock chicken takes far less cooking time than a regular whole roast chicken so don’t be alarmed! If you are a little bit squeamish about opening up a chicken this way then get your butcher to do it for you, who I am sure will happily oblige. However it is great practice to be able to do it yourself.
Preheat the oven to 240C/450F/Gas 8 (220C fan).
Place the chicken breast-side down on a chopping board and using a good pair of scissors cut along each side of the backbone to remove it, cutting through the ribs as you go. Then turn it over and flatten the breast down with the heel of your hand. There will be a small crack which means the bird will then be nice and flat. Then put the bird, breast-side up in a roasting tin.
Use the tip of a small sharp knife to put enough slits all over the breast and legs as there are garlic slices and then push the garlic slices into them. Drizzle with the oil, season well with salt and pepper and then pop into the oven for 30 minutes to get some colour on the skin.
Meanwhile, mix the mustard, honey, chilli powder and thyme leaves together in a small bowl and set aside.
After 30 minutes of cooking, pull the bird out of the oven and reduce the oven temperature to 200C/400F/Gas 6 (180C fan). To help cool the oven down quickly, you can open the oven door and once the thermostat’s red light comes back on shut it. Meanwhile, smear the chicken with the mustard mixture using the back of a spoon. Once the temperature is correct, pop the chicken back into the oven for a further 15 minutes.
Meanwhile, for the sweet potato and mint mash, boil the sweet potatoes for about eight minutes or so (depending on the size of the chunks), or until the potatoes are just tender but not too soft. A couple of minutes before they are ready, melt the butter in a small frying pan on a medium heat and cook the spring onions for two minutes, stirring until softened. Drain the cooked potatoes well and then mash well with a masher. Stir in the spring onions and butter and season well with salt and pepper. Pop a lid on to keep it warm.
To check that the chicken is cooked, insert a sharp knife into the thickest part of the leg, then press the knife down a bit. If the juices run clear, and are not pink, then the chicken is cooked. Once cooked, lift the chicken out of the tray and place on a warmed platter or board and cover with aluminium foil to keep warm.
For the gravy, holding the roasting tin with an oven cloth, tip it up until all the fat and juices run to one corner. Spoon off as much fat as possible and discard. You should be left with around three tablespoons of juices in the bottom of the tin. Pop it on the hob over a low heat and stir in the flour until well blended. Add the wine and stock a little at a time, stirring all the time so that it does not go lumpy. Once all the liquid is added, bring the mixture to the boil and cook for 2-3 minutes, or until thickened, stirring regularly. Pour through a fine sieve into a warmed jug and season to taste with salt and pepper.
Carve the chicken, arrange the slices on a large serving platter and garnish with fresh thyme sprigs. Spoon the sweet potato mash into a serving bowl and scatter the mint over. Serve at once with the hot gravy.
