Heat oven to 220°C.  

Scrub potatoes with a scourer but do not peel.  

Cut slits really close together, down three quarters of the height of each potato.  

Place potatoes on to a baking tray and brush each with a little of the olive oil, sprinkle over some rosemary and season well with salt and pepper.  

Bake for 40 minutes, every 10-15 minutes brush with a little more olive oil.  

Remove and serve once all potatoes are cooked through and nice and crispy.