Preheat outdoor grill to medium. On a charcoal grill, aim to have one even layer of hot charcoal.
Place frozen burgers onto grill. Cover and cook about 6 minutes. Flip and cook another 4 minutes.
Remove cover, add cheese and continue cooking another 2 minutes until cheese is melted.
Place hamburger buns on grill to toast, if desired.
To assemble burgers, spread a generous layer of ranch dressing onto each bun. Top with turkey burger and any more condiments and toppings. Serve immediately.