Country Ham Burgers with Roasted Shallots and Parmigiano-Reggiano Cheese
4 shallots, peeled and cut into very thin slices
5 tablespoons extra virgin olive oil, divided
2 tablespoons balsamic vinegar
3 teaspoon salt, divided
3/4 teaspoon freshly ground black pepper, divided
2 pounds freshly ground beef chuck
2 tablespoons Worcestershire sauce
3 ounces fontina cheese, grated
Oil to brush the grill
4 ounces Parmigiano-Reggiano cheese, shaved using a vegetable peeler
6 Ciabatta rolls, sliced in half
1 cup arugula leaves with stems removed
6 (1/4 inch thick) tomato slices
1 avocado, cut into 12 thin slices
1/4 pound Virgina Ham, sliced as thinly as possible
Preheat a gas grill to medium high heat.
In a small bowl, stir together the shallots, 4 tablespoons of the extra virgin olive oil, balsamic vinegar, 1/2 teaspoon of the salt and 1/4 teaspoon of the black pepper. Transfer shallots to a 12 inch by 12 inch sheet of heavy duty aluminum foil and seal edges tightly forming a large packet. Place the packet on the grill and roast the shallots, turning frequently, until tender, about 20 minutes; keep warm while preparing the patties.
In a large bowl, combine the ground chuck, remaining tablespoon of extra virgin olive oil, 2 teaspoons of the salt, remaining 1/2 teaspoon of black pepper, the Worcestershire sauce and the grated Fontina cheese. Evenly divide the meat into 6 equal portions and shape into patties. Lightly brush the grill rack with oil. Arrange the patties on the grill, close the cover and cook patties for 4 minutes. Using a spatula, turn patties and top each with the Parmigiano-Reggiano cheese, evenly dividing. Close the grill and cook an additional 4 minutes for medium rare or cook until desired doneness. During the last 2 minutes of grilling place the rolls split side down on the grill to lightly toast.
To assemble the burgers, divide the arugula between the bottom roll halves followed by a tomato slice and 2 avocado slices. Sprinkle the avocado slices on each with the remaining 1/2 teaspoon of salt, evenly dividing. Top the avocado on each with a patty, cheese side up. Evenly divide the ham between each, piling into a small mound. Top each with a portion of the roasted shallots and the remaining roll halves; serve immediately.