The Secret of Perfect Cotton Sponge
When everybody's favourite baking teacher and publisher, chef Alex Goh, listed his telephone number in his cookbooks, there's temptation to dial it, like 911 emergencies, when pictures from his books fail to transpire in real life.
In the case of his Japanese cotton sponge cake, rated as "very difficult" at 4 stars, he warns of getting the egg white consistency right, not to over bake nor use too hot a temperature. This cake is prone to collapse and shrinkage. He recommends cooking in a Swiss roll pan at 170 deg Celsius for 25 minutes.
Traditionally, this cake is baked in a wooden rectangular mould. The honey and mirin flavoured version is known as Castella or Kasutera cake. Unlike the modern cake, traditional recipes do not have oil or emulsifier to keep the cake moist. Instead, the invert sugar in honey retains moistness.
Blogosphere has the secret to success: Trim off the ugly bits and photograph an illusion. There you have it, the secret of the perfect cotton sponge.

