Thanks Jim.

The marker paint is about $10 for the tall can. Doesn't exactly rinse off but I just place it in a tub with water and let it soak for a bit before brushing.

With the spray paint I just brush on some old school paint remover. Works great, just messy as all getout.
I'd like to spray tempura as it works excellent when brushed on. Tough to get even coats though and spraying should work, but then there is the spray equipment cleanup.