-Method-

• Cut the potatoes into thin slices. 
• Put the milk in a pot along with 2 chopped cloves of garlic and add the salt, the pepper and the nutmeg.
• Add the potatoes and the leek and boil for 10 minutes.
• Rub an ovenproof baking dish with a clove of garlic and butter it. 
• Put the potatoes with the milk into the baking dish, add half of the grated graviera cheese and mix. 
• Add the salt, the pepper and the heavy cream and cover the surface with the rest of the graviera cheese.
•  Put the butter on top in small pieces and bake in preheated oven at 180*C (350* F)  for about 1 hour.-.