Arrange an oven rack so a broiler pan will be able to sit 2 to 3 inches away from the element and heat the broiler on high (or prepare a hot charcoal or gas grill fire).
Pat the ham steak dry with paper towels and set on the broiler pan (or on a plate for transferring to the grill). In a small saucepan, combine the marmalade, vinegar, rosemary, mustard, soy sauce, and chile flakes. Bring to a simmer over medium heat and cook, whisking to combine, for 2 to 3 minutes. Keep warm. Brush one side of the ham with the glaze and broil (or grill) until the glaze is bubbling and browned, 4 to 5 minutes. Flip, brush on the remaining glaze, and cook the other side for another 4 to 5 minutes. Serve immediately.
nutrition information (per serving):
Photo: Scott Phillips