Amazing (Chocolate Hazelnut Mousse Cake)

My brother just called to clarify the recipe for the Chocolate Hazelnut Mousse cake. I told him to check here. And it wasn't here. I have no idea how it is possible that I haven't made this cake in that long. This is positively horrible of me. I need to make it soon.

Epicurious calls it the Gianduia Mousse Cake, but I can never remember how to spell that (I have trouble with hazelnut (el or le)),  so I 'renamed' it.