Place your bone-in spiral ham on a wooden cutting board and use a sharp chef's knife to score the surface. You'll want to cut 1-inch deep diamond patterns across the entire top dome. This opens up the meat so the glaze can actually penetrate the layers instead of just sliding off the skin. (I tried skipping this once and the flavor stayed purely on the outside, definitely take the two minutes to do it.) You'll see the fat cap pull apart slightly as you cut and the pink meat should peek through. The ham should feel cold but pliable as you work the knife through the tough outer layer. Aim for even spacing between your diagonal lines because it makes for a much prettier final result. Score 1-inch deep diamonds, this creates more surface area for the glaze to cling to later.

Combine the golden honey light brown sugar and Dijon mustard in a small stainless saucepan over medium-low heat. Whisk the mixture constantly for 5 to 7 minutes until the sugar granules completely dissolve into the liquid. You're looking for a smooth syrupy consistency that coats the back of a spoon. If you see it start to bubble too aggressively then turn the heat down to 2 or 3 on your dial. The kitchen will start to smell like warm sugar and vinegar as the ingredients meld together. You'll see tiny bubbles forming around the edges and the color will shift from pale yellow to a deep amber. If the mixture gets too thick too fast it'll be hard to brush on so keep it moving. (I used to rush this on high heat but the honey scorched and tasted bitter, slow and steady is the secret here.) Simmer exactly 6 minutes, gentle heat binds the sugars without burning the delicate honey notes.

Move the ham into a 9x13 ceramic baking dish and pour half of your glaze over the top. Bake at 325°F for about 60 to 75 minutes depending on the size of your cut. You'll want to reach an internal temperature of 140°F before the final glazing step starts. Every 20 minutes use a silicone brush to scoop the juices from the bottom and coat the top again. You'll hear the ham sizzling in the pan and the edges of the spiral slices will start to curl slightly. The glaze will look wet and glossy at first but then it'll start to tack up as the moisture evaporates in the oven. The smell of cloves and ham will become very strong around the 45-minute mark. Don't pull it out early or the center will stay cold and the fat won't render properly. Bake at 325°F internal 140°F, slow roasting ensures the interior is hot without drying out the edges.

Increase the oven temperature to 400°F and brush the remaining glaze over every inch of the meat. Roast for another 10 to 12 minutes until the surface turns a dark mahogany color. Watch it closely through the oven window because the sugar can go from perfect to burnt in under a minute. You want to see the edges of the diamonds getting crispy and almost black in some spots. The glaze will start to crackle and pop as the sugars caramelize under the intense heat. You'll see the glaze thicken into a sticky lacquer that clings to the meat even when you tilt the pan. The oranges in the pan should look charred and the rosemary will be fragrant and slightly toasted. This is where the magic happens and all that patience pays off with a perfect crust. Roast at 400°F for 10 min, intense heat triggers the Maillard reaction for a crispy sweet crust.

Transfer the ham to a clean white ceramic platter and let it rest for exactly 15 minutes before touching it. This allows the juices to settle back into the meat so every slice stays moist and tender. If you cut it immediately the glaze will slide off and the center will be dry. (I used to skip the rest but the first cut leaks half the sauce, don't skip it.) You'll see the glaze set into a firm and sticky shell as it cools slightly. The aroma of cloves and sweet pork will be incredible as you carry it to the table. Use a long carving knife to follow the natural spiral cuts and let the slices fall gently onto the platter. Arrange a few fresh orange rounds around the base for a pop of color and extra juice. Rest 15 minutes before slicing, resting redistributed juices so the ham stays moist through every bite.