How to make
Defrost the dough and roll it out. Roll it out lightly.
Cut out circles using a cup or ring and cut out as many rings.
Coat the circles with beaten egg white and stick a ring on each circle.
Arrange the puff pastry on a baking sheet lined with paper paper.
Bake in a heated oven, until they aquire a golden color.
Take them out and slightly press the core and cool them.
Whip the cream with the milk, according to the instructions on the package.
Fill the vol-au-vent.
Garnish the cream vol-au-vent with blackberries.