1. Preheat oven to 200 °C / 400 °F / gas mark 6
2. Wash a large baking potato and remove any bad bits
3. Stab it all over with a fork (to let the steam out so it doesn't explode) then brush the skin with oil
4. Wrap loosely in tinfoil, leaving a hole at the top and bake for 1 hour - 1 hour 15 minutes, until soft all the way through
5. Mix some sour cream, cheese and chives together for the filling and add when cooked
