Steaming egg custard is usually done with a 1:2 or 1:3 ratio of egg to water, more water if you like it tender, less water if you like it old. Steamed egg custard with thirty to forty degrees Celsius of warm water to do taste better, can not use raw water.
Steaming egg custard avoid adding raw water and hot water, add raw water because there is air in the tap water, the water is boiling, the air out, the egg custard will appear a small honeycomb, affecting the quality of the egg custard, the lack of tenderness, nutrients will be damaged. It is also not advisable to use hot water, otherwise the boiling water will first be hot egg, and then go to the steam, nutritional damage, and even steamed egg custard.