Licensed ice-cube/chocolate trays from Japan.

Ultra Marginal kept recommending these, and I finally got them from HLJ with my recent order, because they were 20% off.

They are nice as a novelty, but not very effective for ice, as they are not easy to fill and keep flat, and the sculpting isn't too prominent... unless you were able to fill them with two colours of water to make the details stand out.
I think they are probably best for chocolate or candy.
They are supposed to be silicone, so should be oven-safe for cookies... but I think I'd do some research on them first before risking it.


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The box they come in is double-sided, with Optimus on red on one side, and Megatron on purple on the other... each with a window to see the tray inside.