Preheat the oven to 325°F (165°C). Place the ham in a roasting pan and pour 2 cups of water into the bottom of the pan. Cover the pan with foil and bake for 2 hours.

Meanwhile, make the glaze. In a small pot over medium heat, combine honey, marmalade, Marukan Seasoned Gourmet Rice Vinegar, tamari, mustard, and butter. Bring to a boil, then reduce heat to simmer while whisking, and cook until thickened, 5-7 minutes. Remove from heat.

Remove the ham from the oven and discard the foil. Increase oven heat to 425°F (220°C). Brush half of the glaze onto the ham, reserving the remaining glaze. Return the ham to the oven and bake for 20-30 minutes, or until golden brown and sticky.

Serve the ham with the remaining glaze on the side.