Roughly cut the butter into small 2cm cubes. Keep the butter cold by storing it in the fridge until needed. Sift the brown sugar, almond flour, all purpose flour and desiccated coconut together. In a stand mixer fitted with the paddle attachment, add all the ingredients and mix at a slow speed. Stop the mixer as soon as the mixture comes together. Spread the dough onto a tray and store in the fridge for 20 minutes.  Pass the dough through the grid of a cooling rack to get uniform sized crumbs for even cooking. Spread the crumbs evenly over a tray and store in the refrigerator until ready to cook. Bake at 160°C for around 16 minutes or until browned.