Step 1

Preheat oven to 180°C/350°F. Line four oven trays with baking paper.

Step 2

Beat butter, brown sugar and vanilla in a medium bowl with an electric mixer until just combined. Add eggs; beat until just combined. Stir in sifted flours, bicarb and xanthan gum, in two batches. Cover; refrigerate for 1 hour.

Step 3

Using wet hands, roll dough into 24 balls. Flatten balls with a fork to 6cm (2½in); place 5cm (2in) apart on trays. Scatter with raw sugar.

Step 4

Bake cookies 18 minutes or until golden. Cool on trays.