... If I had to guess? Jello chocolate pudding made with less milk for the dark layer, and then a whippy chocolate buttercream or mousse for the lighter layer.
It could really be anything, but I felt the need to answer because I 1000% think that is Jello instant pudding. My only evidence is a profound feeling of nostalgia.
Caramel wouldn't be solid enough to become such a thick layer in a cake. If you try to make it thick, you will get it to the consistency of chewy caramel candy - both too sticky and too sweet to use as part of a cake.
My best guess is that you are looking at a layer of gianduja, thinned with something else - or maybe even pure Nutella. The second guess is ...
Looking at the way it is cut, teared and smeared by the spoon in the video my best guess would be that it is some kind of custard or pudding that gets its consistency most probably from yolk and/or starch.
Please be aware that a definitive identification only from a picture will remain an impossible task as no one will be able to see if this mass contains ...
Salami is a generic term referring to all sorts of salt cured or cooked sausage, from a variety of countries and cultures. My guess is that pictured is German fleischwirst or extrawurst (Austrian cousin). The Italian version is mortadella, but typically has white chunks of fat and pistachio nuts.