Spread jam onto half of the biscuits.
Sandwich the jammed biscuits to the non-jammed
Combine the icing sugar, water and butter into a small bowl. If necessary, add more water (the icing should be spreadable).
Spread the icing onto the biscuits.
In a snap-lock bag, place the sugar and red food colouring.
Shake until the sugar has turned pink.
Sprinkle the coloured sugar over the biscuits.