250g butter, at room temperature
1 cup Chelsea Icing Sugar
2 tsp vanilla extract
2 cups gluten-free plain flour
1 cup rice flour
1 egg white, whisked
¼ cup Chelsea Raw Caster Sugar

Preheat oven to 160°C conventional (or 140°C fanforced).
Line 2 oven trays with baking paper. Draw an 18cm circle on each sheet of baking paper.
Using an electric mixer, beat butter, icing sugar and vanilla until mixture is light and creamy. Add flours and stir until well combined and a soft dough forms.
Halve dough and form each into a 3cm-thick round. Roll out 1 round of dough between 2 sheets of baking paper to an 18cm round. Transfer to 1 prepared tray.
Crimp edge of dough with your fingers. Using a sharp knife, mark out dough into 12 even wedges, taking care not to cut through dough.
Brush top with egg white and sprinkle with caster sugar.
Repeat with remaining dough. Bake for 25 mins or until shortbread is light and crisp.
Set aside on trays for 10 mins to cool, then transfer to
a wire rack to cool completely. Cut into wedges (on marked lines) and serve.