Preheat the oven to 220oC/Fan 200oC/425oF/Gas Mark 7.
Place the pine nuts, basil, garlic and olives on a large board, then use a large sharp knife to chop them all together until you have a rough paste. (or use a food processor and blitz)
Season with salt and plenty of ground black pepper.
Unroll the boned shoulder and place skin side down on a board.
Scatter the basil paste over the meat, rubbing it into all the crevices and cut surfaces.
Roll up the shoulder of lamb and tie it together with string at regular intervals to make a neat parcel.
Place the lamb in the centre of a large roasting tin. Roast for 10 mins.
Reduce the temperature to 180oC/Fan 180oC/350oF/Gas Mark 4 and roast for 40 mins.
Remove the roasting tin from the oven, add all the vegetables and toss together until coated in the pan juices.
Roast for a further 40 mins.
Transfer the meat to a board and leave to rest for 10 mins, covered with foil.
Keep the vegetables warm in a serving dish.