Place a metal mixing bowl and metal whisk in the freezer, preheat oven to 325 degrees, grease three 9 by 1 1/2 inch cake pans with melted butter (use two tablespoons from cake butter), place parchment paper in each pan and lightly grease as well (if you only have two pans you can get away with only using two)

Using a double broiler (or two pans) melt the 8 oz of cake chocolate with remaining butter stirring until smooth, then let sit at room temperature (keep double broiler available will be using again)

In a mixing bowl using an electric mixing combine sugar and egg yolks, scrapping down the sides as needed until the mixture is thick and lemon colored about 5-6 minutes total

Whisk 4 egg whites until stiff (do not over whisk)

Fold melted chocolate mixture into egg yolk, stir in 1/4 of egg whites and then fold in remaining whites

Divide batter between pans, cook for 25 minutes (check with toothpick) then allow cakes to come to room temp for 15 minutes while in pans. The cakes will crack and collapse this is okay), after 15 minutes flip cakes and place on large cookie sheet and place in refrigerator for 30 minutes

Using double broiler again, melt 8oz chocolate for mousse, stir until smooth transfer to a metal bowl and set aside

In chilled bowl with chilled whisk, whisk on high until stiff peaks form the heavy cream and sugar

By hand whisk 1/4 of whipped cream into bowl with melted chocolate until smooth, then poor that into the bowl with remaining whipped cream and fold until combined, place in fridge

In a small to medium sauce pan bring heavy cream and butter for ganache to a boil, while this heats place 18oz of semisweet chocolate into a bowl, once to a boil pour over the chocolate and let it rest for 5 minutes, then stir until well combined and smooth. Pull one cup of ganache and chill in refrigerator for atleast an hour, keep remaining ganache at room temp.

Remove cakes from refrigerator, and place one in a 9inch springform pan, evenly spread half of the mousse on cake layer (if you’re only doing two cakes not three put the remainder in the fridge and enjoy as a treat), top mouse with second cake layer, spread remaining half of mousse on second cake, then place last cake on top. Chill for atleast 2 hours.

Remove cake and ganache from refrigerator. Put chilled ganache in a icing pastry bag (any tip preference), remove cake from spring foam pan and coat entire cake sides and top in room temperature ganache. Then decorate top of cake with chilled ganache and place halved raspberries on top for decoration (optional), or shave some white chocolate swirls on top. Can also coat with crushed cookies, nuts, sprinkles, anything that sounds good to you 😃 )