I used to make sugar cubes with our Original Mini mold. It’s volume is a bit like a cube and 1/2 of sugar. I found that when I used meringue powder, it floated to the top of a cup of coffee and looked quite scary, so I omitted the meringue powder and it kind of worked. It sure dissolved better and for my events, it was impressive to have a bowl heaped up of sugar skull heads.
Eventually, I pre-measured the water I needed for 2 cups of sugar, and tinted it with a hefty portion of paste food color. Like ink. If you use clear water, you get white skulls, if you use inky purple, you get purple sugar cubes.
You do the same method of sugar prep, just without the meringue powder. Mix your batch a bit drier than usual because it will be easier to shake or jolt out of the mold. Same strong compaction. You will have the sugar start to stick in the mold after about 5 skulls - then you’ll have to wash and dry your molds again.
The difference is that without the meringue powder, the sugar skull won’t last as long, but who cares, since it’s being eaten in a couple days.
So, just omit it, and use the same water and add a bit more granulated sugar. I’m remembering I got a good finish using the extra fine sugar too.
Since you will have no starch or stickiness going on , you’ll need to let your mixed, moistened bowl of sugar rest a while, like 5 minutes, before you cast the skulls. That will give a chance for the outside of each gradual to dissolve slightly, so upon compaction, it will stick to the neighboring granules.
That’s how you’re going to have great looking sugar skull sugar cubes!
If you want to try smaller ones, then you’ll get the 1 inch Altar skull. But you’ll have to be insane or have lots of patience for that one.
If you want another option, it would be the Oaxaca mini, which will be more sugar than the Original medium skull, but it’s like 2 classic sugar cubes.
The last option is again, a bit larger, which would be the Altar 1 1/2 inch mold
One time I wanted to fancy up the Original mini sugar cubes so I mixed a bit of water in the cap of the yellow, fuchsia and lime green food paste colors and used a little paint brush to paint a flower on top of the heads. Super simple, but it brightened up the bowl of cubes.