Preheat the oven to 350°F (177°C). Prepare a 9x13-inch baking dish by lightly coating it with nonstick spray.
In a saucepan over medium heat, melt the cream cheese until it achieves a smooth and creamy consistency.
Incorporate the dry ranch dressing mix, onion powder, and black pepper into the melted cream cheese, mixing until thoroughly combined. Remove the saucepan from heat once the ingredients are well blended.
Carefully fold in the green onions, shredded chicken, crumbled bacon, and 1 cup of cheddar cheese into the cream cheese mixture, ensuring an even distribution of ingredients.
Place the bottom halves of the Hawaiian Rolls into the prepared baking dish.
Evenly spread the chicken and cream cheese mixture over the bottom halves of the rolls. Subsequently, sprinkle the remaining 1½ cups of cheddar cheese over the chicken mixture. Cover with the top halves of the rolls.
Using a pastry brush, apply the melted butter over the tops of the rolls. Then, evenly sprinkle the grated parmesan cheese and chopped chives over the butter.
Cover the baking dish with aluminum foil and bake in the preheated oven for 25 minutes. Afterward, remove the foil and continue baking for an additional 5 to 8 minutes, or until the tops of the rolls are golden brown.
Allow the sliders to cool for 5 minutes before slicing and serving.