Preheat a covered grill to medium-low, or about 400 degrees F. 

In a large pot of boiling salted water, cook macaroni 2 minutes less than al dente. Drain well, place back in the large pot and season with 1 1/2 teaspoons kosher salt, 1/2 teaspoon black pepper and 1 teaspoon Essence.

Turn the heat to medium and add 6 tablespoons butter, ham, mortadella and heavy cream and bring to a simmer. Add the grated white and yellow cheddar cheeses, a handful at a time, stirring to melt.

Remove the pan from heat and transfer the macaroni to a 9- by 13-inch grill-proof baking dish. Add the breadcrumbs, 1 teaspoon salt, 1/2 teaspoon pepper and remaining teaspoon Essence to a bowl with the remaining 2 tablespoons butter (melted). Toss to combine, then scatter over the macaroni. 

Place baking dish onto the hot grill, cover the grill, and cook over direct heat until the edges are bubbly and beginning to brown, about 25 minutes. Transfer to an area of the grill over indirect heat, and continue to cook until the breadcrumb topping is golden and the macaroni is heated through, 10 to 15 minutes longer. Let cool 5 minutes before serving.