In a large bowl, combine ground chicken, ranch seasoning mix, and cheddar cheese until well mixed.

Shape the mixture into four patties, about half an inch thick.

Preheat the grill or skillet over medium heat and cook each patty for 5-6 minutes per side or until the internal temperature reaches 165°F (75°C).

Assemble burgers by placing patties on buns and topping with lettuce, tomato slices, and a dollop of ranch dressing mixed with mayonnaise.

Serve immediately with your choice of sides.