Scrub the ham well with a stiff brush under running water. Pat it dry with paper towels and place it in a roasting pan skin and fat side up. Heat the oven to 300°F, place the ham in the oven and roast uncovered and without basting. Allow about 20 minutes to the lb cooking time. Very large hams weighing over 15 pounds need only about 16 to 17 minutes per pound.

When the ham is done, remove it from the oven, and using a sharp knife or kitchen scissors, cut off the rind. Score the fat, if you wish, cutting it in long, diagonal slashes in one direction and then crossing these cuts with diagonal slashes in the opposite direction. This makes a diamond pattern in the fat. Push whole cloves into the fat at the corners of the diamond patterns.

Mix 1 cup of brown sugar with 2 teaspoons of dry mustard and moisten with a little of the ham fat from the roasting pan. Spread this mixture over the top of the ham and return it to the oven. Increase the heat to 400°F and cook until the sugar has glazed and the fat turned crisp.