1. Preheat your grill to medium-high heat.
2. In a mixing bowl, combine ground turkey, garlic powder, onion powder, salt, and black pepper. Mix well.
3. Form the mixture into 4 equal patties.
4. Brush each patty with olive oil to prevent sticking.
5. Place the patties on the grill and cook for about 5 minutes on each side, or until fully cooked through.
6. During the last minute of cooking, place a slice of cheese on each patty to melt.
7. Toast the burger buns on the grill for a minute or until lightly browned.
8. Assemble the burgers with lettuce, tomato, onion, and your choice of condiments.