Preheat oven to 325°F. Place a rack in a roasting pan.

Make the glaze: Combine brown sugar, cola, apple cider vinegar, soy sauce, Dijon and grainy mustard, ground ginger, onion powder, crushed red pepper, and kosher salt in a medium saucepan.

Bring to a simmer over medium heat, stirring until sugar dissolves. Reduce heat and simmer 6–8 minutes until slightly syrupy. Stir in 2–3 tablespoons of crushed pineapple juice if it looks too thick. Remove from heat and set aside.

Remove ham from packaging and place cut side down in the roasting pan.

Spoon crushed pineapple evenly into the slices and over the ham.

Brush the entire ham with about one-third of the glaze. Tightly tent the ham with foil.

Warm the ham for approximately 10–12 minutes per pound, or until an instant-read thermometer inserted into the thickest part reads 140°F.

Remove foil, baste with another third of the glaze, and return to oven uncovered for 10–15 minutes.

For a sticky, caramelized finish, broil on high for 1–3 minutes—watch constantly to avoid burning.

Let the ham rest 10 minutes before carving. Spoon any pan juices and remaining glaze over slices when serving.