Trim lamb shoulder of excess fat and place in a roasting tray.
Place grated pear, sage leaves, oil, salt and pepper in a small bowl and toss to combine. Spread over lamb shoulder. Leave to marinate for 30 minutes at room temperature, or up to overnight in the fridge.
Preheat oven to 200°C, pour ½ cup water into the base of the roasting dish and cover tightly with foil. Cook lamb for 2 hours or until tender enough to shred with two forks. Shred lamb and season to taste.
Toss parsnips in a little oil, salt and pepper and roast for 40 minutes until golden brown and crisp at the edges.
Combine ingredients for slaw and toss gently to combine.
Fill buns with slaw and top with shredded lamb. Serve roast parsnips on the side.
Pour water from tray before shredding meat in the pan, or place lamb on a chopping board for a more stable surface.
After shredding, check the seasoning of the meat and add a squeeze of lemon, salt or pepper if desired.
Lamb can be cooked and shredded in advance. Reheat to serve.
2 hours is the minimum cooking time to be able to shred the lamb. If you have the time, leave the lamb in the oven for another 30 minutes to 1 hour. It will only get better and easier to shred.
Try different ingredients in the slaw such as beetroot and apple.