Pre-heat oven to 180°C and line 2 baking trays with baking paper.
In a large bowl, cream margarine and sugar, then add remaining ingredients and stir to combine.
Place heaped teaspoons of mixture onto prepared trays and bake for 20 minutes. Remove from oven and cool on tray.
To prepare icing, place icing sugar and cocoa powder in a medium bowl. Add coconut milk and stir until thick and creamy. Spoon teaspoons of mixture over the cooled biscuits and top with sprinkles if desired. Allow icing to set before serving.