1. Mix first 5 ingredients in medium bowl.
2. Add ground turkey and generous amount of pepper.
3. Form mixture into two thin patties.
4. Pour thin layer of oil into heavy medium skillet over medium heat.
5. Add patties. Cover and fry until just cooked through (3 minutes per side).
6. Top each patty with cheese. Cover and cook until just melted.
7. Transfer to plates. Top with onion slices and serve.