Preheat the oven to 180 C (350 F) and line a couple of trays with baking paper.
Place the flour, ¾ cup of parmesan, pesto, salt, onion powder, chilli and butter into a food processor. Pulse the machine on and off until a dough forms.
Gather the dough together and give it a light knead.
Scoop rounded teaspoons of the dough and roll them into balls. Place them on the baking trays and press them down into 2 inch diameter rounds.
Sprinkle the remaining 6 tablespoons of parmesan over the shortbread.
Bake for 20 minutes, until golden. Makes 24 cheese cookies.
Recipe by Butter Baking at https://www.butterbaking.com/2012/04/23/parmesan-chilli-shortbread/