Preheat the Oven: Set your oven to 375°F (190°C). Line a baking pan with foil for easy cleanup and lightly coat it with nonstick cooking spray.
Assemble the Sliders: Slice the slider buns in half horizontally, keeping the tops and bottoms connected. Place the bottom halves in the prepared pan. Spread a layer of pizza sauce evenly over the bread, followed by shredded mozzarella cheese and pepperoni slices. Sprinkle with a pinch of Parmesan and Italian seasoning for extra flavor. Place the top halves of the buns over the filling.
Make the Garlic Butter: In a small bowl, mix together the melted butter and garlic powder until combined. Spoon or brush the mixture evenly over the tops of the slider buns, making sure to coat them completely for that delicious, golden finish.
Bake: Cover the pan with foil and bake in the preheated oven for 12–15 minutes, or until the cheese inside is melted and the tops are lightly toasted. Remove the foil for the last 2 minutes if you want a crispier finish.
Serve: Remove from the oven and sprinkle additional Parmesan cheese on top if desired. Let cool slightly, then cut along the bun lines and serve warm.
