Preheat the oven to 350°F. Line a large baking sheet with aluminum foil. In a large bowl, combine the ground chicken, panko, onion, parsley, garlic, lemon zest, eggs, parmesan cheese, 1 teaspoon kosher salt, and pepper. Lightly mix together, using your hands or a large spoon. Transfer to the lined baking sheet and shape into a loaf, approximately 2” high and 4” wide, making the loaf as uniform in size as possible. Smooth the top and place on the middle oven rack. Bake for 60 minutes, set the timer for 30 minutes.