In a hot frying pan, quickly brown the lamb in a bit of olive oil. Remove the meat and place in 2 quart saucepan, with lid. Sauté the onions, along with the garlic in a bit of oil until limp. Add to the lamb. Cover the lamb with stock and add the curry powder, ginger, salt and pepper. Simmer, covered until all is tender, about 1 1/2 hours. Thicken with cornstarch and water mixture.