1. Line a baking tray with baking paper. Preheat the oven to 200C/400F/mark 6.
2. On a surface sprinkled liberally with sugar, roll out the pastry to a rectangle of thickness 3-4mm.
3. Sprinkle some more sugar evenly over the top of the pastry. Roll up one side of the pastry towards the centre, stopping at the middle, so half the pastry has been rolled. Repeat on the other side, again working towards the middle. Gently press the sides together, then wrap in cling film and refrigerate for 30 minutes.
4. Slice the rolled pastry into pieces roughly 1cm thick. Lie on the prepared tray and bake for 10-15 minutes.