Take the pork roast out of the fridge and leave on the bench to warm slightly while you prepare the rub.
Rub: Combine all the spices. If there is a large range of grain sizes, briefly put in a coffee grinder or food processor and gently pulse to get an even consistency. Sprinkle the rub over the pork and leave for 20 minutes, the rub should slowly become moist all over.
Glaze: Combine the BBQ and jam then mix well. If the jam is cold and thick you can heat on the stove or in the microwave so in mixes more easily.
To Cook: Preheat the BBQ (or oven) to 150 degrees C. Add the pork in a roasting tin and let cook. After 3 hours, check the pork. The meat should be cooked throughout. If done, remove and coat with the glaze. Return to the BBQ and cook for a further 15 minutes or until the glaze sets.