Trim some of the fat on the ham and peel away hide. Score ham in criss-cross fashion; Rub mustard mixture over meat. Place in a roasting pan and pour 1 cup of water into the bottom of the pan.
Bake ham, uncovered, about 45 minutes. Meanwhile, heat coconut oil in a large skillet over medium-high heat. Add apple rings, maple syrup, sugar and allspice.