1Preheat oven to 350 degrees F (175 degrees C). Place ham in a large baking dish.
2Bake in the preheated oven for 45 minutes. Whisk brown sugar, ginger ale, mustard, and cinnamon together in a bowl; brush over ham. Continue baking ham until the meat pulls away easily from the bone, about 45 more minutes. An instant-read thermometer inserted into the center should read 145 degrees F (63 degrees C).
Footnotes
Cook's Note:
I make my ham the day before not cooking it fully. The day of the event, usually the next day, I heat with a little water to steam it. I place the ham in a warmer as I serve buffet-style. I make a double batch of glaze, I then pour the glaze over ham.