Preheat oven to 325 °F.

Combine all glaze ingredients in a small saucepan on medium heat. Bring to a gentle simmer, whisking occasionally, until sugar is melted, about 3-4 minutes. Remove from heat and set aside.

Score the ham in a diagonal crosshatch pattern. Starting from one end close to the bottom, cut about 1/2 inch into the ham in a diagonal straight line across the ham. Repeat making lines 1″ apart on the entire ham. Rotate the ham and repeat diagonally from one side to the other.

Place the ham in a large oven-safe dish or high rimmed metal pan. Fill with 1/2 inch of water and pour 1/4 cup of glaze over the ham. Cover ham/pan with foil, sealing the ham in entirely.

Bake for 45 minutes, basting with the glaze at the 20-minute mark. After 45 minutes remove from the oven, baste with glaze, and return uncovered to the oven for 15-20 additional minutes, or until ham reaches internal temp of 140 °F. Baste again in the last 5 minutes.

Remove ham from the oven and let sit for 10-15 minutes tented with foil before serving. Baste just before slicing and serving.