Cook the bacon until crispy, then drain on paper towels and crumble into small pieces.
In a large bowl, combine the chopped chicken, bacon, cheddar cheese, red onion, celery, and chives.
Add the ranch dressing, garlic powder, onion powder, salt, and black pepper.
Mix everything together until evenly coated.
Slice the sandwich rolls in half and lightly toast them if desired.
Place lettuce leaves on the bottom half of each roll.
Add tomato slices if using.
Divide the chopped chicken mixture evenly among the rolls.
Top with the remaining bread and serve immediately.