Preheat the oven to 350°F (175°C).
In a bowl, combine the shredded chicken with BBQ sauce until evenly coated.
Slice the slider buns in half horizontally without separating them individually.
Place the bottom half of the buns in a greased baking dish or sheet pan.
Spread the BBQ chicken mixture evenly over the buns.
Top with shredded cheese and sliced red onions.
Place the top buns over the filling.
Brush the tops with melted butter mixed with garlic powder and onion powder.
Bake for 12–15 minutes until the cheese is melted and the tops are golden brown.
Remove from the oven and garnish with fresh parsley.
Slice into individual sliders and serve warm.