Before starting, allow the ham to sit at room temperature for about 30 minutes. This helps it cook evenly and prevents the glaze from burning while the center warms.
Remove the rind if needed and lightly score the fat in a diamond pattern. Place the ham in the roasting pan and add pineapple juice to the bottom. Cover it with foil and bake so it gently steams and becomes tender.
In a saucepan, melt butter, then mix in honey and brown sugar until smooth. Once the ham is heated through, remove the foil and generously brush the glaze over the surface. Make sure it seeps into the scored cuts for maximum flavor.
Return the ham to the oven uncovered. Continue baking while occasionally brushing with glaze and pan juices. The surface will turn golden, sticky, and beautifully caramelized. Remove from the oven once fully heated and glossy.