01 - In a large bowl, combine ground turkey, breadcrumbs, egg, onion, garlic, Dijon mustard, Worcestershire sauce, salt, and pepper. Mix gently until just combined, avoiding overworking the mixture.
02 - Form the mixture into 4 equal-sized patties, approximately 1/2 inch thick, ensuring uniform thickness for even cooking.
03 - Heat a grill or skillet over medium heat. Lightly oil the surface to prevent sticking.
04 - Cook the patties for 5 to 6 minutes per side, or until fully cooked with an internal temperature reaching 165°F.
05 - During the final minute of cooking, place a slice of cheese on each patty and cover to allow the cheese to melt completely.
06 - While the patties cook, butter the cut sides of the buns and toast them on the grill or skillet until golden brown.
07 - Spread mayonnaise, ketchup, or mustard on the toasted buns as desired. Layer with lettuce, tomato slices, and red onion.
08 - Place the cheese-topped turkey patties on the prepared buns and serve immediately while warm.