First, let’s acknowledge the irony: we’re reheating a ham that’s already been cooked to hell and back. Why? Because cold, rubbery ham is a crime against holiday spirit. The USDA says any fully cooked ham (like spiral-cut, city ham, or smoked country ham) just needs to hit 140°F (60°C).
But wait—your grocery store label might scream “cook to 165°F!” Ignore it like a bad infomercial. That 165°F number is for uncooked hams (like fresh ham) or leftovers. For a pre-cooked ham, 140°F is your sweet spot—hot enough to melt the glaze, cool enough to keep it juicy.
Side comment: if you roast it to 165°F, you’ll get a ham that tastes like salted cardboard. Don’t be a hero.
How to Hit That 140°F Bullseye
Set your oven to 325°F—this is the Goldilocks zone for ham. Too low, and you’ll be waiting until next Tuesday; too high, and the outside turns into leather. Place your ham cut-side down on a rack in a roasting pan, and add about a half-inch of water to the pan bottom. Why? Steam, baby—it keeps the meat from drying out while the glaze caramelizes.
Here’s the math: a fully cooked ham needs about 10–14 minutes per pound at 325°F. So a 10-pound ham? That’s roughly 1.5 to 2.5 hours. But please, please use a meat thermometer. Your gut feeling is a liar.
Insert the thermometer into the thickest part of the ham, avoiding the bone if it’s bone-in. Bone conducts heat weirdly, and you’ll get a false reading. Aim for the center of the meat, not touching fat or bone.
