Roll out the pastry dough on a lightly floured surface until it is a rectangle 2.5 mm (⅛ inch) thick. Cut it into 6 rectangles, each 12 x 7 cm (5 x 3 inches), and put them on a baking sheet. Chill for 30 minutes. Bake in a preheated oven, 200°C (400°F), Gas Mark 6, for 15 minutes until the pastry is puffed and golden. Transfer to a wire rack to cool.
Put the cream and vanilla pod in a saucepan and heat gently until it reaches boiling point. Remove from the heat and scrape the seeds from the vanilla pod into the cream (discard the pod). Immediately stir in the chocolate and continue stirring until it has melted. Cool, chill for 1 hour until firm, then whisk until spreadable.
Split the pastries in half crossways and fill each with white chocolate cream and raspberries. Serve dusted with sifted icing sugar.