Slice the brussel sprouts thinly with a mandolin or sharp knife. Either in a blender, or a bowl with a whisk, mix the shredded garlic, anchovy paste, mustard, vinegar, Worcestershire, and lemon juice (and capers, if you're going vegetarian). Whisk/blend until fully mixed, then slowly add the olive oil, mixing well as you add. Finally, mix in the parmesan cheese, and salt and pepper, to taste. Toss the sprouts with the dressing and set aside for 5-15 minutes. On a grill set to 350ºF/175ºC, or on a pan set to medium heat, cook the prosciutto pieces for approximately 3 minutes on each side. Remove from heat, let cool, then cut into small pieces. Add the prosciutto to the salad and toss. Top with parmesan flakes and fresh ground pepper. Serve.