Wash the lamb shoulder and place it on a tray.
Make cuts on both sides with a knife.
Peel and cut the garlic cloves in half. Stud the joint of lamb with cloves and garlic in the cuts made by the knife.
Sprinkle with sea salt. Tear the rosemary leaves from the stem and sprinkle them on both sides. (lamb and rosemary - a classic combination - just about to be made better with a little twist!)
Peel the onions, half, and then roughly chop them.
Place the onion on a roasting tray - I recycled my foil tray used for my making roast potatoes for our Christmas dinner.
Place the seasoned and prepared lamb shoulder on the onion and spritz with oil - I used oil very sparingly and find using oil from a spraying bottle ideal for this recipe.
Then pour a generous glug of ruby port wine onto the lamb - I didn't measure this but added enough to ensure that the meat is totally wet and there is enough to make a gravy - allow for enough so that you can baste the meat at least twice while it is roasting in the oven. Roughly 500ml or one pint should suffice.
Pre-heat the oven to 220° C.
Cover the roasting tray with a foil such that the foil covers the edge of the tray like a proper lid.
Roast in the preheated oven for 2 hours, basting at least twice to allow the meat to cook thoroughly and ensure you get a succulent soft roast that simply falls off the bone.
After 2 hours check the roast and adjust cooking time accordingly - I needed about 40 mins more for a soft roast.