Preheat oven to 200 degrees Celsius.
Cut enough slits for the halved or quartered garlic cloves
Press one piece of garlic and one rosemary leaf into each slit.
Place the lamb in a large roasting pan and sprinkle evenly with the remaining rosemary leaves. Drizzle over 1 tablespoon of oil.
Season with salt and pepper and roast in the oven for 15 minutes.
Remove the pan from the oven and place the potato in a single layer around the lamb. Drizzle the remaining oil over the potato and season before returning to the oven to cook for 1 (one) hour for medium or until cooked to your liking.
Use this time to steam some vegetable of your choice to go with your roast lamb and roast potatoes.
Remove the lamb from the oven and transfer it to a plate and cover with foil and let it rest for 10 minutes.
Turn the potatoes and return to the hot oven for another 10 minutes while the lamb rests. Remove from the oven and place in a bowl and cover with foil to keep warm.
Make a gravy of choice using the juices in the roasting pan.
Thickly slice the lamb, serve with roasted potatoes and mixed steam vegetables and gravy.
ENJOY!