I have not tried the cupcake thing, sounds good. That’s new to me, but the tea thing yes. didn’t have fancy equipment, mom just made a solution thing out of powdered suger and stuff and pipped it out in a design on wax paper and baked it for a bit. I have done it a few times since I was a kid, but prefer the cube. It didn’t look as good as the pic you posted.
It’s apparently very easy to make, with the right tools; and you can make it in all sorts of shapes and sizes, for all kinds of decorating. You can buy what you need, in many different types, from lots of different places:
https://www.youtube.com/watch?v=2LBCLWEIlVI