Preheat the oven to 150˚C.
Lightly grease two shallow 20cm round cake tins.
Sift the flour, cornflour, salt, Gregg's Ground Cinnamon and
Nutmeg into a bowl. Rub in the butter until the mixture is the
consistency of fine breadcrumbs, then add the caster sugar.
Knead the mixture until it is smooth. Knead in the pistachio
nuts.
Place the mixture into the cake tins and press the top firmly
with the back of a large spoon. Crimp the edges by pinching the
mixture between your finger and thumb. Prick the top with a
fork.
Bake in the preheated oven for 35-40 minutes or until the
shortbread is a pale gold colour.
Remove from the oven and sprinkle with extra caster sugar. Mark
each shortbread into 12 wedges with a sharp knife. Cut into pieces
while still warm.