Preheat oven to 200 degrees Celsius / 400 degrees Fahrenheit and line an oven tray with parchment paper/baking paper.
Roll out the puff pastry on a lightly floured surface.
Use a cookie cutter/pastry cutter to cut out bases for the mini vol au vents from one half of the puff pastry sheet and place them onto the baking tray.
Cut out the second half of the puff pastry sheet, but then use the smaller cookie cutter to cut a smaller circle from the center to create a ring of puff pastry.
Stack each ring of puff pastry on top of one of the bases.
Brush a beaten egg wash over each vol au vent and use a fork to prick the center circle to prevent it from puffing up.
Bake vol au vents for 10-15 minutes until golden brown and glossy. Cool vol-au-vent cases on a wire rack.
Notes
Always preheat the oven and use an oven thermometer to check it is at the right temperature.