Mix the spice paste ingredients in a bowl to combine.
Lightly score the fat of the lamb into a criss-cross pattern, then deeply pierce the meat a few times and put in a large bowl.
Using clean hands, rub the marinade into the lamb.
Cover and transfer to the fridge for 6 hrs, or overnight.
When ready to cook, bring the lamb to room temperature, place in a tin that fits it snugly and season well.
Preheat the oven to gas 7, 220°C, fan 200°C.
Pour the wine into the tin around the lamb and cover with a double layer of foil, sealing around the edges.
Put in the oven and reduce the temperature to gas 3, 160°C, fan 140°C.
Roast for 4 hrs, basting in the juices a few times, until the meat pulls away with a fork.
Uncover the lamb, drizzle with the honey; cook for 30 mins.
Transfer the lamb to a board and cover with foil and a tea towel; leave to rest for 20 mins.
Transfer the juices from the tin to a bowl and skim away any fat.
Serve the lamb shredded from the bone, with the warm juices spooned over.
