Preheat the oven to 150°C fan and line a baking tray with baking paper.
In a large bowl, combine the plain flour, corn flour, icing sugar and salt.
Add the softened butter and mix until a soft dough forms.
Turn the dough onto a silicone mat or lightly floured surface. Roll it out to approximately 1.5cm thick. Cut into fingers using a large knife, pastry cutter or pasta roller cutter.
Leave the cut shortbread on the mat or board and refrigerate for approximately 10 minutes. Chilling the dough makes the pieces easier to transfer without losing their shape.
Transfer the shortbread to the prepared baking tray, leaving a little space between each piece.
Bake for approximately 30–40 minutes, or until pale golden around the edges.
Transfer to a wire rack and allow to cool completely.
Melt the chocolate in the microwave in 15-second bursts, stirring between each, or melt gently using the bain-marie method.
Dip approximately half of each shortbread biscuit into the melted chocolate. Place onto baking paper and leave until the chocolate has completely set.