In a mixing bowl, combine ground turkey, garlic powder, onion powder, oregano, salt, and pepper. Mix until just combined.

Form the mixture into 4 equal patties, making a slight indentation in the center of each patty to prevent puffing during cooking.

Preheat the grill to medium-high heat and lightly oil the grates.

Place the patties on the grill and cook for about 5-7 minutes on each side, or until the internal temperature reaches 165°F (74°C).

If using cheese, add a slice on top of each patty during the last minute of cooking to melt.

Toast the burger buns on the grill for 1-2 minutes until golden.

Layer lettuce, tomato, pickles, and the turkey patty on the bottom half of the bun. Add ketchup and mustard if desired, then top with the other half of the bun.