Preheat your oven to 350 degrees F and line a large rimmed baking sheet with foil. Place an oven-safe oven rack on top if you wish.
Place the ham on the rack and score a grid-like pattern, cutting down about 1/2 inch.
In a medium bowl, whisk together the beer, brown sugar, maple syrup, mustard, cornstarch, salt, allspice, cayenne pepper, Chinese five spice and black pepper. Taking about 1/3 of the mixture, brush the entire ham generously.
Place the ham in the oven, uncovered and bake for 1 hour. Remove from oven and brush another 1/3 of the glaze on top and place back in the oven. Bake for an additional hour or until the top is brown and crisp. Remove from heat.
In a small saucepan, add the remaining 1/3 of the glaze. Heat over medium-low heat until the alcohol has cooked out and the glaze is thick. Remove from heat and pour into a serving bowl.
Slice the ham to your liking and serve warm with glaze.