Heat grill or broiler.

Combine turkey, oats, garlic, Worcestershire sauce, oregano, salt and pepper in large bowl; mix lightly but thoroughly. Shape into 6 large patties, about 1/4-inch thick.

Place one mozzarella ball in center of each patty; shape burger mixture around cheese so it is completely hidden; reshape into patty. (Note: If small fresh mozzarella balls are unavailable, substitute large fresh mozzarella balls, cut into 1/3 to 1/2-ounce pieces. Or, a 3-ounce chunk of part-skim mozzarella cheese, cut into 6 pieces, can be substituted for fresh mozzarella.)

Grill or broil burgers 4 inches from heat 5 minutes on each side or until centers are no longer pink (170°F). Arrange burgers on bottom halves of buns; top with roasted pepper pieces, watercress and bun tops. or your own favorite toppings e.g.. mayonaisse, relish, tomatoes