An epi of The Great British Baking Show featured a multilayered cake made by pouring a thin layer in a [tall?] round cake tin, broiling it for a minute or so, then pouring another thin layer on top, and broiling that for t+ to get a darker layer, and another layer, etc, alternating the broil times to get the light/dark layer effect effect.
I'm remembering them as 1/4" layers. That, and one engineering inclined baker measured the total batter, and figured out how much to use for each layer, rather than eye-balling it.
Precision is important when you are making even layers!
The closest I've come to something like that was when I was making Dobos torte, and had to bake eight or ten thin little layers of genoise batter on the backs of 8-inch cake pans. Baked each a few minutes then peeled it off, on to the next one. Had to make sure the batter was an even amount.