Combine all the garlic, rosemary, oil, salt, pepper and curry powder into a paste and rub into the lamb shoulder and its cavity. Truss with butcher's twine and place in the refrigerator overnight. The following day preheat your oven to 325° Fahrenheit. Remove lamb from fridge. Take a large stock pot or dutch oven, place on stove and turn on high. Once pot is scorching hot, add 3 tablespoons of canola oil. Add the lamb shoulder and sear on all sides till golden brown. Deglaze with 2 cups of dry white wine and add chicken stock. Cover with lid or tight fitting foil and place in the oven. Roast for 4 to 4½ hours till meat is tender and pulls away from itself. Remove pot from oven, take out the lamb from pot, keeping the liquid, and remove the twine. Turn on broiler and broil lamb till outside gets nice and crusty. Reduce the liquid in the pot by half, season to taste, strain and set aside. Serve.
