Pre-heat oven to 160°C (conventional) / 140°C (fan-forced/convection).
Place butter and sugar in the bowl of an electric mixer and whisk for a few minutes until creamy.
Add flour, rice flour and salt. Mix well with a wooden spoon until thoroughly combined.
Scoop into a round or square ceramic pie/cake pan (7.5-8inches base measurement). Press down the doughs in an even layer with your fingers. Indent the edges with your fingertips to get a scalloped pattern.
Using a sharp paring knife, score the dough all the way to the bottom into 16 triangles (if using a circular pan) or 24 squares (if using a square pan).
Prick the dough evenly using a fork. Cover the top of the pan with a cling wrap and chill in the fridge for 20 minutes.
Remove the cling wrap and place the pan in the oven. Bake at 160°C (conventional)/140°C (Fan-forced) for approximately 25-28 minutes.
Towards the end of the baking cycle watch to see if the shortbread has reached the golden shade you like and pull it out sooner if you feel it is dark enough. It will continue to darken slightly as it cools.
When you pull the shortbread out of the oven and it is hot, cut the dough again with the paring knife over the previously scored guidelines. Allow the shortbread to cool completely. Go over the cuts once again with the knife to ensure the pieces are separated. Lift one out gently and then separate the rest.
Store in an airtight container in a cool corner of your kitchen for up to 4 days or in the fridge for up to 2 weeks.
Make It Gluten Free - Substitute regular plain flour with gluten-free flour.You can substitute rapadura sugar with coconut sugar or brown sugar.