Cream the butter and icing sugar together until pale and fluffy then beat in the vanilla
Stir in the cornflour and flour and enough milk to make the mixture pipeable.
Use a 1cm star nozzle and pipe lines of about 7cm on 3 lined sheet pans.
Bake at 180C/160FAN/350F/Gas4 for about 15 minutes until golden.
For the buttercream beat the butter together with the icing sugar and cocoa.
Sandwich together the biscuits with the chocolate buttercream.
Sprinkle with icing sugar if liked.
Notes
Tips:
Make sure that the butter is soft for the buttercream and the biscuits - this makes it easier to mix with the icing sugar.
Avoid over filling the piping bag as it makes it easier to grip the bag with a smaller amount
Use reusable parchment as the biscuits are delicate and will just slide off easily.
Disclaimer:The nutritional information provided is approximate and is calculated using online tools. Information can vary depending on various factors, but we have endeavoured to be as accurate as possible.