Melt butter in a frypan and cook leek gently for 5 minutes until softened. Allow to cool.
To make the cheese filling, combine grated Perfect Italiano Traditional Parmesan, Ricotta, egg, cooked leek, nutmeg and seasonings in the frypan with the melted butter.
Cut each pastry sheet into 9 squares and place a spoonful of cheese filling onto each. Fold each square over to form a triangle, press edges firmly to seal and enclose filling and press the two ends together.
Place on a lined baking tray, brush with extra egg and sprinkle with caraway seeds.
Bake at 200°C for 15 minutes or until golden and cooked.