Preheat oven to 400. Wash and wipe the potatoes. Prick with a fork and place on

a baking sheet.  Cook the potatoes in the oven for 60 to 75 minutes or until they are soft inside and crisp on the outside.

Remove from the oven,  Cut each potato in half lengthwise. Scoop out the soft insides into mixing bowl. Take care not to damage the skins.  Mash the potatoes well with fork. Add butter and season.  Place the skins on the baking sheet. Chop the ham and put some into each shell. Spoon into the potato. Sprinkle the grated cheese on the potatoes. Put them back into the oven and cook for a about 15 minutes or until golden brown.