Sliced Baked Potato. Preheat the oven to 400. Slice across the potato, being sure to stop before you reach its bottom. Open the potatoes’ crevices and shove the Parmesan and butter, alternating between the two. Drizzle oil on top of the potatoes. Season with salt and garlic powder. Bake for about 60 minutes. After about 45 minutes, drizzle cream over the top and top with grated cheese. Return to oven for the last 15 minutes.