Preheat your oven to 325°F. Not 350°F, not 300°F. 325°F is the Goldilocks zone for ham. It’s warm enough to get things sizzling but gentle enough to keep the meat juicy.
Place your ham cut-side down in a roasting pan or a deep baking dish. Add about a half-inch of water, apple juice, or even broth to the bottom. This keeps it from drying out and makes your kitchen smell like heaven.
Cover it tightly with foil. Think of the foil as a cozy blanket for your ham. No one wants a dry ham, and foil is your shield against tragedy.