Preheat the oven to 180°C fan.

Put the chopped onions, garlic, ginger, spices and herbs into a food processor and blitz until finely minced. Add the oil, vinegar, 1¾ teaspoons of salt and a generous grind of pepper and blitz into a coarse paste.

Pat dry the lamb and pierce the flesh all over using a small, sharp knife (about 10–12 times). Coat the lamb well with all the paste. You can cook it right away or leave it to marinate, refrigerated, for 3 hours to overnight.

Put the onion wedges, cinnamon sticks, cardamom and figs into a large, ovenproof cast-iron saucepan (28cm in diameter) for which you have a lid. Alternatively, use a large, high-sided roasting tin and some foil to cover. Top with the lamb, fatty side up, then pour the chicken stock into the pan (but not over the lamb) and bake uncovered for 45 minutes. Lower the heat to 140°C fan, baste the lamb with the juices, then cover with the lid or foil and roast for 4½ hours, basting 3–4 times throughout. The lamb should be quite tender at this point. Turn the heat back up to 180°C fan. Remove the lid (or foil) and cook for 30 minutes more, or until the lamb is well browned and the sauce has reduced slightly. Check it at the 20-minute mark.

Gently remove the lamb, leaving it to rest on a baking tray. Pour the contents of the saucepan into a large, shallow platter or dish that has a slight lip and top with the lamb.

Make the fig and pistachio salsa. Combine the chopped figs with the pistachios, lemon juice and the herbs. Spoon this all over the lamb and serve with the lemon wedges alongside.