Spiral sliced hams can be cooked in a variety of ways including baking or roasting. Different methods are used to produce the cook's desired texture and flavor. Spiral sliced hams are fully cooked during the curing and smoking process, so they can be eaten even without cooking.
To bake a spiral sliced ham, place the ham fat side up in an appropriately sized pan. Place the ham in a cooking bag, or cover it with foil to help it retain moisture. Cook the meat at 275 degrees Fahrenheit for the appropriate time, usually about 15 minutes per pound. Remove the ham when it's done, and turn the oven up to 425 degrees Fahrenheit. Baste the ham with a glaze of your choice, and return it to the oven for about 10 minutes.
Some cooks claim that a spiral ham is more tender when cooked in a roaster. To use this method, place the ham in the roaster fat side up. Add water until the bottom 1/2 inch of the ham is covered, and roast at 350 degrees Fahrenheit until the internal temperature reaches 140 degrees Fahrenheit on a meat thermometer. Coat the ham with the glaze of your choice about 30 minutes before it is finished cooking.