Pre-heat the oven to 325º F and butter a 9-inch square cake pan.

Using a food processor, process the sugar until it becomes superfine sugar – pulse it for about 30 seconds. Add the butter and process until smooth, light and fluffy, scraping down the bowl of the food processor a few times during the process. Add the flour and salt and pulse the food processor until the mixture can be squeezed together in your hand to form a dough. Add the chocolate chunks and pulse one last time for about 15 to 20 seconds until the chocolate is evenly dispersed.

Transfer the mixture to the buttered cake pan and press the dough into the pan, using a round can or drinking glass to smooth it out at the end.

Chill the dough in the refrigerator for 15 minutes and then transfer to the oven and bake for 45 minutes or until very lightly golden brown.

Remove the shortbread from the oven and cut the shortbread into the desired shape with a knife. Let it cool. Once cool, cut the shortbread one more time into the desired shape, following the score marks and enjoy.