Make sure all the ingredients are at room temperature. Cream the butter and sugar together in a bowl until pale and fluffy.

Sift the flour, groundrice and salt together onto the creamed mixture and stir in, using a wooden spoon until the mixture resembles breadcrumbs. I tend to do this gently to try to keep mixture really light.

Gather the dough together with your hand and turn onto a clean worksurface. Knead lightly until it forms a ball, then lightly roll/shape into a sausage abotu 2 inches (5 cm) thick. Do all this a gently as you can.

Wrap in cling film and chill in fridge for at least a couple of hours (I often do this over night)

unwrap the roll and slice into discs, about 1/3-1/2 inch (7-10 mm) thick.

(optional) Roll the edge of each biscuit in golden sugar.

Place the biscuits on two baking sheets lined with greaseproof paper ... spread them out a bit as they will expand.

Bake at 190C (375F) for 15-20 minutes, depending on the thickness, until very pale golden.

On removing from the oven sprinkle with caster sugar. Leave on a baking sheet for 10 minutes, then transfer to a wire rack to cool.