No Bake Tank Cake

sandwich the maderia cakes together with butter icing and cut a sloping bit on the front. cut 4cm of each swiss roll and save one bit for top. cut the other slice in half and save one bit for lid. put the swiss rolls next to the maderia cakes. stick the buscuit and the large swiss roll cut off to the top with butter icing. cover the whole thing in green butter icing. cover the small bit you left for a lid in green icing then stick it to top. then decorate