Preheat the oven to 220'C.
Melt the butter.
Sprinkle the work surface with a little sugar. Roll the puff pastry thinly to about 3 mm thick and a sheet roughly 15cm x 30cm.
Brush the inside with a little of the melted butter and sprinkle liberally with sugar. Fold the long sides in, so that they almost meet in the middle. Dust again with sugar and then fold the edges inwards along the central crease. Wrap tightly in clingfilm and chill for 30 minutes.
Using a sharp knife, cut the pastry into 24 slices, place on a baking sheet and sprinkle with more caster sugar.
Bake for 10 minutes.
Turn each palmier over and bake for a further 3-4 minutes until crisp and golden brown all over.
Whilst still hot, sprinkle with more sugar and transfer to a wire rack to cool.
«Vary the flavours of these little biscuits by adding flavours such as ground cinnamon or mixed spice.»