Trim ends from Brussels sprouts and halve or quarter.
Pour the melted butter into a 9x13-inch casserole dish, tilting the dish to evenly coat the bottom. Sprinkle on the parmesan cheese. In a small bowl, mix together the garlic powder, paprika, salt, and pepper, then sprinkle over the cheese.
Lay the Brussels sprouts, cut-side down, on top of the cheese in a single layer. Try to leave a little space between each sprout.
Bake for 20 minutes. Let the pan cool for at least 5 minutes before carefully removing sprouts to a serving dish (tongs or a flat spatula will work well). Any cheese left behind can be scraped up and sprinkled on top for serving.