Stir in the heavy cream, wine, garlic powder, and cayenne pepper, letting it gently simmer. Pour the sauce over the roasted onions and sprinkle generously with Parmesan cheese. Cover with foil and roast for 20 minutes, then uncover and roast for another 5–10 minutes until the onions are caramelized and the cheese turns golden brown. Serve hot and enjoy this sweet, savory, creamy, and unforgettable dish that pairs perfectly with roasted meats or stands out on its own as a luxurious side