Dust the 30cm drum with icing sugar and sprinkle with a small amount of water. Knead
The 15cm cake will need about
Lift the sugarpaste with your hands, place it over the cake and gently smooth, covering the cake and drum. Do not stretch, and work as quickly as you can, as it will dry out. Cut away any excess, provided it is still clean, and seal in a polythene bag. Leave the 3 cakes overnight.
Now insert 4 dowelling sticks into the large cake, spacing them to form the corners of a square just within where the 20cm cake will sit. Push down each stick until it hits the drum, and mark with a pen about 1mm proud of the surface. Remove each stick, score with a knife at the mark, snap and discard the excess. Replace each in its hole.
Spread a spoonful of royal icing into the centre of the largest cake, remove the 20cm cake and drum from its thin board and place centrally on top of the larger cake, resting the drum on the hidden dowels. Repeat the dowel placing process with this middle tier to add the top cake, again using a spoonful of royal icing to keep it steady.