Let ham sit at room temperature for 2 hours. Preheat oven to 325°F (163°C). Place ham cut-side down in roasting pan.

In a medium saucepan, combine apricot preserves, honey, brown sugar, Dijon mustard, and unsalted butter. Heat over medium heat until simmering, about 3–5 minutes, then simmer for 1 minute.

Brush ⅓ of the glaze over the ham. Cover with foil and bake in the oven for about 2 hours, until internal temperature reaches 130°F (54°C).

Remove foil, increase oven temperature to 425°F (218°C). Brush another ⅓ of glaze over ham and bake uncovered for an additional 10 minutes.

Apply the last ⅓ of the glaze, roast uncovered for another 10 minutes, or until the surface is bubbly and brown. Internal temperature should be at least 140°F (60°C).

Remove ham from the oven, transfer to serving dish, and let rest for 15–20 minutes. Strain pan juices to serve with ham.