In a large bowl combine the ground turkey, roasted red pepper, feta, garlic, oregano, red onion, parsley, and optional dill and pepperoncini, if using. Season with freshly ground black pepper to taste. Mix with clean hands or a rubber spatula until everything is fully incorporated.
Divide the meat mixture into four equal portions and shape into large patties placing on a nonstick surface such as wax paper or parchment. Sprinkle kosher salt over the tops of each patty. (For grilling, I recommend misting both sides of the burgers—and the grill—with oil spray because they can really stick!)
Coat a large sauté pan with oil spray and warm over medium-high heat. (Alternatively, preheat an indoor or outdoor grill pan coated with oil spray.)
Place the burgers in the pan and cook for ~6 minutes per side, or until the burgers are no longer pink in the center or 165˚. After flipping, sprinkle kosher salt over the tops of the second side as well. (Pro tip for outdoor grilling: the burgers will start to loosen slightly from the grates when they are ready to flip. You are looking for nice char marks and caramelization.)
Serve in mini pitas layered with crisp lettuce, thinly sliced tomato and a dollop of optional Tzatziki Sauce.
Nutrition information is calculated using a leading industry software. That being said, brands can vary, and there may be slight fluctuations in the numbers.