From Patisserie: A Masterclass in Classic and Contemporary Patisserie this is the entire Citrus slice:
My wife did most of the steps, I helped with a few - got to heat eggs and sugar to 99f then wipe to a ribbon for the first time.
We don't make the macron to go on top of a single slice like in the cookbook, but we don't sell slices either. Individual slices tend to look better but this entire long thing is pretty cool
It's built out of many layers in a frame designed for entremets.
Here's what the cake looks like for a single slice:
