Crush cinnamon and cloves with a pestle and mortar.
Toast the crushed spices in a dry pan until fragrant.
Add torn red chillies to the pan and fry briefly.
Blend cooled spices with remaining masala ingredients into a fine paste.
Rub the masala over the pork and refrigerate for several hours.
Preheat the oven to 180°C.
Brown the marinated pork in a roasting tin with oil on the hob.
Roast the pork in the oven for 30 minutes.
Reduce oven to minimum, cover tightly with foil, and cook for 3-5 hours.
Shred the cooked pork using two forks.
Serve the shredded meat in lettuce leaves with coleslaw and coriander.