Preheat the oven to 180C/160C Fan/Gas 4. Place the lamb shoulder skin-side up in a large roasting tin.
Mix the olive oil, garlic, cumin, ginger, coriander, paprika, turmeric, black pepper, cayenne pepper and salt together in a small bowl until well combined. Using a sharp knife, make small but deep incisions all over the lamb shoulder. Rub the olive oil mixture all over the meat, working it into the incisions (this will enable the meat to absorb all the flavours).
Cover the tray tightly with kitchen foil and roast the lamb for 3 hours, basting the meat every 45 minutes with the juices in the tray. Remove the foil and roast the lamb for a further 35–45 minutes, or until the skin is crisp and golden and the meat is tender and falling off the bone.
Cover the lamb with kitchen foil and leave to rest for 15 minutes.
When the lamb has rested, use two forks to shred the meat. Garnish the meat with chopped mint leaves and flaked almonds and then serve immediately with bread on the side.