If you have a magimix put all the ingredients for the biscuits in together and mix until they form a soft ball. If making these by hand rub the butter into flour and add sugar. Gather the mixture together and knead well.
On a floured surface roll out the mixture until it is about 5mm thick. Cut shapes and place on a greased baking tray. Gather the remaining mixture, knead together again and roll out to cut more shapes. Repeat until all the mixture has been used up.
Bake in a moderate oven, 180 degrees Celsius or Gas mark 4, until biscuits are pale brown (about 15 minutes).
Remove and cool on a wire rack. We normally sprinkle the cooled biscuits with a little icing sugar and serve. However, if you want to be more festive they can be decorated with a topping of your choice.
For the icing, mix the sugar and water until the icing is free of lumps. Spread a thin layer of icing on each and sprinkle with a decoration of your choice. Allow the icing to set.