To spatchcock the chicken, lay it on a board, breast-side down, and cut down either side of the backbone using kitchen scissors to remove it (this can be frozen to use in stock). Make two slashes in each side of the chicken breasts, and one in each of the legs and thighs. Flip the chicken over so it’s cut-side is down, then gently press down over the breasts using your hands to flatten it.

Toast the fenugreek, cumin and coriander seeds and the peppercorns in a dry frying pan over a medium heat until fragrant, about 5 mins – watch closely to ensure they don’t burn. Grind in a spice grinder or using a pestle and mortar, then combine with the turmeric, paprika and 2 tsp salt in a bowl. Stir into the yogurt.

Put the chicken in a roasting tin and pour over the spiced yogurt, rubbing it into the slashes and over both sides of the bird. Cover with baking parchment and chill overnight.

The next day, light the coals of the barbecue and, once the flames have died down, move them to one side of the grill. Put the chicken breast-side up on the side without coals, with the legs closest to the heat source. Close the lid, open the vents and grill for 30 mins.

Turn the chicken over, close the lid again and cook for another 30 mins. Move the chicken directly over the coals, breast-side up, cover and cook for 10 mins. Turn over and cook for another 10 mins, then check the temperature where the thigh attaches to the body – it's ready when the probe reads 70C or the juices run clear. Remove to a tray, cover loosely and rest for 10 mins before carving.