4 oz (100g) plain flour

2 oz (50g) rice flour or cornflour

4 oz (100g) butter

2 oz (50g) caster sugar

Preheat oven to 180 C / 350F/ Gas Mark 4. sieve the flour and rice flour or cornflour on to a board. Cut the butter into pieces and mix with the sugar in a separate pile. Work the butter and sugar together with the hands and gradually work in the flour to make a firm dough. Form into a ball and roll out on a lightly floured surface to a circle 8 in (20cm) in diameter. Lift on to a greased baking sheet and pinch the edges between finger and thumb. Prick lightly all over with a fork. Bake for 10 minutes. Lower oven heat to 160 C/ 325F/ Gas Mark 3 and continue baking for 25 minutes. Leave on the baking sheet and mark into triangular wedges. After 5 minutes, lift on to a wire rack to cool. Sprinkle with a little caster sugar before serving.