Preheat the oven to 450 degrees F. Adjust the oven racks to the top and bottom positions.
Place the potatoes on a sheet pan, pour 3/4 cup water over the potatoes and cover tightly with foil. Bake on the bottom rack until tender, about 30 minutes. Remove from the oven, drain any remaining water and let rest 8 minutes.
Drizzle 3 tablespoons oil over the potatoes, making sure they are evenly coasted. Space the potatoes evenly on the sheet pan and, using a potato masher, flatten the potatoes to about 1/2 inch thick (about 1/2 the length of your thumb to the first joint). Sprinkle with salt and pepper. Drizzle the remaining 3 tablespoons olive oil over the potatoes and roast on the top rack for 15 minutes. Remove from the oven and sprinkle with the cheese. Roast on the bottom rack until golden brown, about 20 minutes. Remove from the oven and top with the sour cream and scallions. Serve immediately.
Think of your favorite baked potato items and just add it on top. Bacon would be delicious, as well as chopped up broccoli with shredded Cheddar cheese. Sometimes for dinner, I just make the potato plain and poach an egg on top. Easy dinner with great leftovers.