Thaw and Dry: Remove the frozen chicken nuggets or tenders from the freezer and let them thaw completely at room temperature for about 10-15 minutes, then pat them dry with paper towels to remove excess moisture.
Season the Chicken: Place the thawed chicken pieces on a plate and season both sides lightly with a pinch of garlic powder and Italian seasoning.
Prepare for Baking: Lightly grease a 9x13 inch baking dish with butter, then arrange the seasoned chicken pieces in a single layer at the bottom of the dish.
Create the Base: Slice the Hawaiian rolls in half horizontally and place the bottom halves into the prepared baking dish, nestling them together to fit snugly.
Layer the Chicken and Sauce: Arrange the seasoned chicken nuggets or tenders on top of the roll bottoms, then spoon the marinara sauce evenly over each piece, using about 3/4 cup total.
Add the Cheese: Top each chicken piece with a slice of mozzarella cheese, cutting the slices as needed to fit the slider size, then sprinkle the grated Parmesan cheese over the entire dish.
Butter and Bake: Melt the remaining butter and drizzle it over the roll tops, then place them on top of the cheese layer, and bake in a preheated 350°F oven for 20-25 minutes until the rolls are golden brown and the cheese is melted and bubbly.