Steamed bread made with rice flour instead of wheat flour makes bread that doesn't go hard as quickly, so I recommend this method.
After a few experiments I tried adding more sugar to this recipe to improve the flavour.

When steaming the bread, please make sure the steamer is steaming before adding the bread.
Steaming the bread over high heat will give them a nice texture.
You can make 4 muffin cups instead if you'd prefer. in that case, steam them for 15 minutes. Recipe by papiraki