In a food processor blitz the hazelnuts until broken into small pieces (you do not want it to be too fine).
Dice the butter straight from the refrigerator and rub into the flour. This may take a few minutes but be patient with it as this will ensure a very 'short' shortbread. When the flour and butter resembles fine breadcrumbs, add the sugar and mix thoroughly.
Line a tray with parchment paper and press the mix into the tray. It should be no more than 1/2 a centimetre thick. Scatter the hazelnuts on top and gently press into the dough. Bake in the oven for 16-18 minutes then transfer to a wire rack. The shortbread will appear to be soft and not cooked, but will firm up as it cools.
«When your shortbread has cooled down you can break it into shards and dip in chocolate. Place back on the wire rack and chill in the fridge for 3 minutes to allow the chocolate to set.»