The hazelnuts would not skin, after trying to "toast and rub" which took most of a night for the genoise, I opted for the "boil and wash" method for the prailine which worked much better but did leave the nuts soggier, which was fine for the praline but good to note for the future. I also used a double foil pan for baking for stability which lead to a underbaked middle which, upon cutting into (2, not 3) layers, had to rebake and therefore slightly dry out the cake itself. The praline buttercream was increidble and definitely made the cake...the 3 sticks of butter also broke my hand beater, and therefore everything post-beating the butter was done by hand; it was fun to get down on the floor and really work the ingredients by hand, especially the whipped cream.
Overall the cake was a big hit, it looked beautiful and tasted good if not a little dry. I would love the chance to make this again and can't wait for the next challenge!