Thawing at room temperature can.

Heating ham slices. You want to heat your ham the same way you initially cooked it. Follow instructions on the bag for preparation. Or use an oven roasting bag;

Alternatively, use an oven roasting bag and prepare according to the bag’s instructions. If heating ham from the freezer, move it to the refrigerator to thaw 24 hours prior. Cook or heat the ham as close to serving time as possible.

(place whole ham on its side.) cover. Preheat the oven for about 10 minutes at 325 °f, and place the tray on the middle rack.