In a large bowl, mix ground turkey, bread crumbs, onion, egg whites, parsley, garlic, Worcestershire sauce, salt, and pepper until just combined. Don't overmix or the burgers may become tough.

Divide the mixture into 12 equal portions and form into patties about 3/4 inch thick. Press a slight depression in the center of each patty to prevent it from puffing up during cooking.

Preheat grill to medium-high heat or heat a large skillet over medium heat with a tablespoon of oil.

Cook the turkey patties for 5-6 minutes on each side, or until the internal temperature reaches 165°F (74°C) and juices run clear.

If adding cheese, place a slice on each burger during the last minute of cooking.

Toast the hamburger buns lightly if desired.

Serve turkey burgers on buns with your favorite toppings.