2. Scrub the potatoes and dry them well then pierce the skin in several places with a fine skewer.
3. Put the potatoes directly onto the rack in the centre of the oven and cook for about 1 hour.
4. Test the potatoes with a skewer to check if the centre is completely soft.
5. Remove from the oven with care – they will be extremely hot – cut a cross in the top of each potato with a sharp knife and push in at the sides so that the top opens out. Serve with butter or other toppings of your choice.