heat oven to 350. in a large bowl, cream butter and 1c of sugar til light and fluffy.beat in 4lg eggs, than 1 1/2c of flour, then vanilla til smooth. lightly coat the bottoms of 7 (9inch) round pans w/ cooking spray. weigh batter and divide by 7. (dont forget to subtract weight of bowl). that is # of how many ounces of batter goes into each pan. very important to make same size. you will bake for 7 minutes or until edges are very lightly brown. DO NOT OVER BAKE!!! remove from oven. loosen layer and envert onto a cake rack. cont until all batter is used.
FOR THE FILLING:
melt semi sweet and unsweetend choc and set aside. in lg bowl beat 4 sticks of unsalted butter on low for 2min., then on med for 3, then on high for 5 min. place egg whites and 1c of sugar in a in a db boiler over med heat. whisk gently to 120 degrees. transfer to mixing bowl and whip it til stiff peaks form. (whip on high). fold melted choc into butter then fold in egg whites until there is no more white showing. refrigerate until ready
place on cake layer on rack and set over a pan to catch any dripping. mix 2/3 cup of sugar and water in small heavy saucepan. DO NOT STIR. cook until sugar dissolves, boils, darkens. swirling pan continue to boil until golden brown. pour immediatly over cake layer you set aside on rack. quickly mark glaze into 16 equal wedges w/o cutting all the way through. that is your top piece.
take layers one at a time and put 1/8inch of filling between each layer. use carmel one as topper. frost the sides and decorate the top anyway you like to. then enyoy it