Save leftover baked potatoes in the fridge and grate them the next morning. Heat butter or margarine in frying pan and add grated potatoes. Cook one side. Turn with spatula and cook other side.
Make sure the butter is good and hot when you put in your grated potatoes. Don't turn them until they are golden brown. When ever I bake potatoes for dinner I always try to have leftovers so I can have hash browns for breakfast. Sometimes I serve hash browns with sloppy joe for dinner.