Set your oven to 150 C / Gas 2. Put your sugar and margarine in a large mixing bowl and cream together with a wooden spoon or a electric hand mixer.
Then fold in the flour and mix well and add your 2 eggs and mix together until creamy with no lumps.
When mixed put out 12 cases into a bun tray and divide the mixture equally.
Place the tray in the oven on the top shelf and leave for 10 to 15 minutes, or until firm and golden brown on top. And while it's cooking set out a cooling rack.
When cooked place on the cooling rack and when the bun tray has cooled down, take out the bun and leave to cool.
When cold, make your icing.
Put 100g of icing sugar into a medium sized mixing bowl, then get a jug of cold water and keep pouring in tiny drops of water and keep mixing, until a thick creamy paste, and if you want coloured icing add food colouring.
Then add decorations, but add the icing on the buns, one bun at a time because the icing sets really quickly.