Put the leg of lamb into a large roasting pan. Bruise the leaves of 2 or 3 sprigs of rosemary and sprinkle them over the meat. Add plenty of pepper and 1 tablespoon honey. Rub the mixture into the meat with your hands. Then rub half a lemon over the joint, squeezing the juice on to the meat as you do so. Do not add any salt. Leave to marinate for 4 to 24 hours.
2.
Peel and quarter the potatoes, then arrange them in a single layer round the lamb. Squeeze lemon juice over the potatoes -- use at least half a lemon, or up to one and a half lemons for a strong citrus flavour. Carefully pour 1/4 pint water into a corner of the roasting pan, then sprinkle over the potatoes and lamb about 2 tablespoons chopped fresh rosemary, at least 1 teaspoon each fresh chopped thyme and oregano, and some salt and pepper. Drizzle on 1-1/2 teaspoons honey and 1 tablespoon olive oil, then dot with 1 oz butter. Bake at 425 F (220 C) gas mark 6 for a further 1 to 1-1/4 hours. The ingredients will become gilded and will burnish to a rich brown in places. Lift the meat and turn the potatoes occasionally, and if necessary, add a little boiling water to the pan to prevent drying out.
