Wash, salt, and oil 6 large baking potatoes. Bake until done. Slice in half lengthwise and scoop out insides. Arrange shells on platter. Mash pulp with 1 stick butter and 1 carton sour cream; add milk to thin into mashed potato consistency. Season with salt, pepper, garlic powder, and dash of cayenne pepper. Add 1/2 pound shredded Cheddar cheese. Stuff into shells and top with more cheese. Heat in oven or microwave when ready to serve.