Preheat oven to 400°. Scrub and pierce potatoes. Rub with oil if desired. Bake until tender, 50-75 minutes. When cool enough to handle, cut each potato in half lengthwise. Scoop out pulp, leaving a thin shell; set aside. Reduce oven temperature to 375°., In a small skillet, saute onions in 1/4 cup butter until tender. In a large bowl, mash potato pulp. Stir in sauteed onions, cream, sour cream, salt and pepper. Fold in cheese. Stuff into potato shells., Place on a baking sheet. Melt remaining butter; drizzle over potatoes. Sprinkle with paprika. Bake until heated through, about 20 minutes.