Next time, I need to either double the batch or find an 8x8 or 9x9 pan to make them in for thicker bars. These were fantastic, despite their thinness.
I've resumed trying to solve the puzzle of how to make coconut-flavored frosting with non-artificial flavoring that results in coconut flavor in the frosting. Still good, but not coconutty. Next time, I need to halve this recipe until I figure this one out.