Beat the butter, vanilla essence, sugar and egg in a small bowl with an electric mixer until light and fluffy.
Transfer the mixture to a large bowl and stir in the sifted flour, coconut and currants.
Shape 2 level teaspoons of mixture into a ball and place onto a greased oven tray.
Flatten with your hand or a cup until about 5 mm thick. Repeat and allow about 5 cm between cookies.
Bake in a moderately hot oven for about 10 minutes, or until lightly browned.
Once cooled spread the cookies thinly with icing.
Add all the ingredients for the icing in a bowl and stir over hot water until the icing becomes spreadable. Add enough milk to give a thick paste.
