For the cones: Whisk the egg and egg white together in a large bowl. Whisk in the sugar until it is well blended. Whisk together the flour, cinnamon, nutmeg, ginger, and salt, then whisk the dry ingredients into the wet ingredients, being careful to whisk out any lumps. Stir in the melted butter. Prepare the cones according to the manufacturer's directions on your waffle cone maker. (Waffle cones can also be found at most supermarkets.)
Fill the bottom of the cone with some stuffing. Stick pieces of turkey into the stuffing around the inside of the cone. Place a small scoop of mashed potatoes on top. Cover with gravy and some cranberry sauce. Sprinkle the pistachios over the top.