Now, take a small bowl and combine, pulp, egg, milk, mayonnaise, half cup of shredded cheese, salt and pepper. Mash the ingredients together, and then scoop this mixture into the potato shells. Top the stuffed potato shells with bacon, remaining shredded cheese and onion rings. Place these stuffed potatoes in a baking pan, and again bake the potatoes for half an hour at 375 degree Fahrenheit.