The hind leg is one of the four primal cuts of pork, the other three being the loin, shoulder and belly. Also called the ham -- and often by that name already cured -- a full pork leg can weigh about 20 lbs. Unless you're cooking for a crowd, use one of the smaller roasts into which a leg is commonly cut -- the shank or the sirloin, preferably the shank, advise the editors at "Cook's Illustrated." Choose a roast with skin on, which will help keep the meat moist.
Preheat the oven to 500 degrees Fahrenheit.
Use a sharp knife to score the surface of the roast into a diamond pattern. Cut the skin and fat only, avoiding the meat.
Rub the roast all over with a mixture of herbs, if desired. The editors of "Cook's Illustrated" suggest a mixture of sage, parsley, garlic, olive oil, salt and pepper blended to a paste in a food processor. Or just rub the roast generously with salt and pepper to taste.
Put the roast on the rack in the roasting pan, and cook at 500 F for 20 minutes.
Reduce the oven temperature to 350 F and continue roasting until a meat thermometer registers 150 F, about 2 to 2-1/2 hours.
Remove the roast and allow it to rest another 30 minutes or until a meat thermometer registers 155 to 160 F. Carve and serve.