Heirloom Tomato Burger with Prosciutto, Mozzarella and Balsamic Reduction
1.5 lbs ground Naturally raised, grass-finished sirloin
1 tbsp. Worcestershire sauce
1 tbsp. smoked salt (such as alterwood or applewood smoked salt)
1 tsp. freshly ground black pepper
2 tbsp. organic dark brown sugar
vegetable oil, for grilling
1/4 cup aged balsamic vinegar
6 slices proscuitto
12 oz. fresh buffalo mozzarella, sliced into 6 1/4″ discs
1 large organic heirloom tomato, sliced into 6 1/4″ discs
6 whole-grain hamburger buns
1. Preheat your grill on medium-high heat, ensuring the grates are clean.
2. In a large bowl, combine the ground sirloin, Worcestershire sauce, smoked salt and freshly-ground black pepper. Use your hands to mix the ingredients until just combined.
3. Evenly divide the ground sirloin mixture into 6 patties, about 1″ thick. Dust both sides of each patty with brown sugar.
4. Pour the balsamic vinegar into a small skillet or saucepan and place directly on the grill. Bring to a boil and cook about 4 minutes, or until it has reduced and thickened slightly. Set aside.
5. Oil the grill grates lightly with vegetable oil to prevent the burger from sticking. Grill the burgers, flipping once, about 4 minutes per side for medim-rare. In the last one minute of cooking, top each patty with a slice of mozzarella. Set aside to rest 5 minutes before assembling the burger.
6. Meanwhile, grill the prosciutto slices until slightly crisp, about 1 minute, then flip and grill for another 30 seconds. Set aside.
7. Lightly toast the cut sides of the hamburger buns on the grill for about 1 minute. Check for toastiness – if you prefer a more-toasted bun, turn each piece 90-degrees and grill for an additional minute.
8. Assemble the burger in the following order, from bottom to top: Bottom bun, sirloin patty with cheese, heirloom tomato. Drizzle with the balsamic redution, then top with the crispy proscuitto and the top bun.