Combine all ingredients in a bowl then stir to combine. Store in the refrigerator while preparing burgers.
For the Lamb Burgers:
In a large bowl add bread crumbs, parmesan cheese, parsley, sun dried tomatoes, egg, milk, salt and pepper then stir to combine. Crumble ground lamb on top then mix with hands until just combined and divide mixture into four portions. Press each portion into a thin burger. Lay two slices of prosciutto cris-crossed on a cutting board. Place burger on top then fold over ends of prosciutto.
Preheat grill to medium high. Spray both sides of burgers well with nonstick spray then place prosciutto covered side down and grill for 4-5 minutes. Carefully flip then grill for another 3-4 minutes. Let rest for 5 minutes then place on a bed of arugula, spoon bruschetta mixture on top, and then serve.