Preheat your oven to 400°F and lightly grease a sheet pan or line it with parchment paper.

If needed, warm your meatballs in the microwave or on the stovetop until heated through. Stir in the marinara sauce so the meatballs are evenly coated.

Place the Hawaiian rolls directly on the pan. Use a shot glass or small round cutter to press a hole into the top of each roll, going about three-quarters of the way down. Be careful not to press all the way through.

In a small bowl, mix the melted butter with garlic powder, parsley, and Italian seasoning. Brush the rolls generously with the garlic butter, coating the tops, edges, and inside each hole.

Add a little shredded mozzarella into each pocket, then press in a warm marinara-coated meatball. For extra saucy sliders, add a small spoonful of marinara on top of the meatball. Sprinkle a bit more mozzarella over each meatball and gently press it down so it stays in place.

Bake uncovered for 10 to 15 minutes, or until the cheese is melted and the tops are golden brown.

Let the sliders cool slightly before serving so everything holds together when lifted.