Thoroughly combine cream cheese, sun-dried tomato, and garlic salt in small bowl. Set aside.
In a large bowl, mix ground beef with salt and Worcestershire sauce.
Divide meat into 12 equal portions (about ⅓ cup each) and flatten portions into 4½-inch round patties.
Place 2 tablespoons of filling on 6 of the patties and spread to within a ½ inch of the edge.
Cover with remaining 6 patties and pinch the edges closed.
Broil or grill patties.
Serve on rolls with optional lettuce and onions.