Preheat to 350 degrees.
Slice the rolls in half horizontally. Don’t pull them apart. Place the bottom half in the center of a baking sheet.
In a medium bowl, mix the shredded chicken with BBQ sauce until evenly coated.
Spread the BBQ chicken mixture evenly over the bottom rolls. Top with sliced red onion and the shredded cheeses. Place the roll tops on.
In a small bowl, stir the melted butter, dried parsley, and garlic salt. Then brush liberally over the top of the rolls.
Cover with foil and bake the BBQ chicken sliders until the cheese is melted and the tops are golden, about 10 to 12 minutes.
Carefully slice the rolls with a serrated knife, and serve warm with some extra BBQ sauce on the side. Enjoy!