Preheat oven to 350°F. Spray a rimmed baking sheet or 9x13-inch pan with cooking spray. Set aside.

In a large bowl, add the shredded chicken, bacon, ranch dressing, cheddar cheese, parmesan cheese, and green onions. Stir to combine, adding a bit more ranch dressing if the mixture seems too dry. Season with a generous pinch of salt and pepper; mix to combine.

Use a serrated knife to cut the rolls in half like a bagel or hamburger bun and place the bottoms in the prepared baking dish.

Spread the chicken mixture evenly over the rolls; add the tops of the rolls.

In a small bowl, mix together the melted butter with the garlic powder, onion powder, dried parsley, and dried dill. Brush the seasoned butter over the tops of the rolls.

Bake for 25-35 minutes, or until the filling is hot and the cheese is melty. Check the sliders after about 20 minutes; if the tops are getting too toasted, tent the top with foil to prevent further browning while the sliders continue baking.

Serve hot.