This is a streamlined version of the famous Thai steamed pumpkin custard. You know, the kind where you steam a whole pumpkin along with the custard filling; the kind that isn't as easy to make as many recipes want you to think. You get pretty much the same taste out of this version without nearly as much fuss. This appeals to a lazy person like me who's always looking for a faster, easier way to do everything.
Just as I recommend kabocha squash or calabaza pumpkin for Thai pumpkin in sweet coconut cream, I also recommend these same types of squash/pumpkin for this dessert. They have the best texture when steamed and their mild flavor lends itself to Thai desserts very well.