Preheat grill pan or large sauté pan to medium-high heat.

In a medium bowl, whisk together the egg and 2 tablespoons of the Italian dressing.

Add in turkey, 1/3 cup feta cheese, 1/4 cup chopped red onion, parsley, and breadcrumbs to the egg mixture and mix well.

Using hands, shape turkey into 6 patties about 1/3 cup meat mixture each.

Turn heat down to medium heat and spray pan with cooking spray. Cook turkey patties over medium heat for 5-8 minutes on both sides, or until fully cooked.

To serve, place a burger on a large lettuce leaf and top with 1 teaspoon Italian dressing and sprinkle each lightly with remaining feta cheese and chopped red onion.