Step 1

Put sugar, butter and sifted flours and baking powder in separate piles on a clean surface.

Step 2

Knead butter and sugar together.

Step 3

Gradually draw in the flour, kneading well.

Step 4

When the mixture is a stiff paste, break into two pieces.

Step 5

Roll out each piece into a circle that's a little over 1 cm (or 1/2 inch) thick.

Step 6

Pinch edges and dust with a little extra sugar on top.

Step 7

Bake in a slow oven until golden. (I bake mine in a fan-forced oven at 140 degrees celsius for about 35 minutes.)