Black lime (loomi) and lemon spatchcock chicken

Method

1. Pat the chicken well dry with paper towels, then flip it over, breast side down, so the backbone is facing you. Use a pair of poultry shears (or a very sharp knife) to cut along each side of the backbone to remove it (save it for making stock or gravy!). Flip the chicken back over and push down firmly on the breast to flatten the bird – you want to snap the wishbone. Pat the chicken dry again and season all over with 1½ teaspoons salt, using your fingers to push some salt in between the skin and flesh. Set aside.
2. Use your hands to press down on the black limes to roughly crush them. Open them up and pick out and discard any pips (these are bitter). Add the black lime to a spice grinder and blitz to finely crush (you can also do this in a small food processor with a large quantity of black limes). Measure out 1½ tablespoons (store any extra in a sealed jar) and add to a small bowl with the cumin, paprika, oregano, sugar, ¼ teaspoon salt and a generous grind of black pepper and mix well. Rub this all over the chicken (try to get some underneath the skin as well), making sure it is well coated. Transfer to a plate and refrigerate, uncovered, for at least a couple of hours, or up to overnight. If the latter, remove the chicken from the refrigerator an hour before roasting.
3. When ready to cook, remove the chicken from the refrigerator and then preheat the oven to 190°C fan/gas 6½.
4. Place the garlic halves, the lemon slices and 100ml of water in a large cast-iron skillet. Place the chicken on top, breast-side up, and drizzle all over with the oil. Transfer to the oven and roast for 25 minutes, then carefully remove and use a spoon to baste the chicken. Return to the oven, rotating the dish, and roast for another 15 minutes.
5. Meanwhile, melt the butter in a small pan. When ready, remove the chicken and pour the butter all over the skin. Return to the oven for about another 10 minutes or until the juices run clear and the internal temperature reads 75°C on a digital thermometer. Set aside to rest for about 10 minutes, then carefully transfer the chicken to a large platter.
6. Pick out 3-4 lemon slices and the roasted garlic. Squeeze the garlic flesh into a medium bowl, discarding the papery skins, and use a fork to mash until smooth. Finely chop the lemons, peel and all, and add to the bowl along with the yoghurt, the crushed clove of garlic, the parsley and a tiny pinch of salt.
7. Pour the pan juices and remaining lemon slices all over the chicken and serve with the yogurt alongside.