Parisian Bistro Burgers

Preheat grill to medium high heat. Combine ground beef, 3 Tbsp Blackberry preserves, Worcestershire sauce, 1 tsp black pepper and 2 tsp of the fresh rosemary. Form into 6 patties. Season both sides of the burgers with 1 teaspoon each salt and pepper. Set aside until onions are nearly done. Melt butter in a skillet on the grill, sauté onions in butter over medium high heat for 3-4 min or until soft. Sprinkle with brown sugar, cider vinegar and remaining rosemary. Cook, stirring often until onions are caramelized and very soft. Stir in remaining blackberry preserves, chocolate chips, and remaining black pepper. Keep Warm Place burgers on grill and grill over medium high heat 4-6 min per side, or until internal temperature is 160° F. Place 2 slices of cheese on top of each burger, close lid and cook just until cheese melts. Remove burgers, place under foil tent to keep warm. Let rest 5 min. Toast Buns on grill. Stir together Dijon mustard, mayonnaise, and crushed garlic. To assemble burgers: spread Dijon mixture generously on inside of top half of the Kaiser buns. Place burger with melted cheese on bottom half, top with blackberry onion gastrique and top of bun. Serve immediately.