Prepare Sponge Cake: Preheat oven to 325°F Line 17 by 12 inch jelly roll pan with waxed paper.
In very large bowl, combine 2 1/2 cups sugar, ground almonds and flour. Add 8 eggs, one at a time, mixing thoroughly after each addition. Add melted butter; mix briskly for 30 seconds.
In medium bowl with electric mixer at high speed, beat egg whites with remaining 1/2 cup sugar until stiff peaks form. With rubber spatula, gently fold beaten whites into flour mixture in 3 or 4 additions, pour batter into prepared pan, spreading evenly with spatula. Bake 15 to 20 minutes, or until top of cake is golden brown. Cool in pan on wire rack.
Prepare the Peanut Butter Cream: In medium saucepan over medium heat, combine the sugar and 7/8 cup water; bring to a boil. Reduce heat to low; cook until syrup reaches 240 F., “soft ball” stage, on a candy thermometer.
Meanwhile, in large bowl with mixer at medium speed, beat 10 egg yolks and whole egg. Add sugar syrup in a gradual stream; beat 5 minutes. Add butter; beat 5 minutes longer. Add peanut butter; beat until mixture is smooth. Set aside.
Prepare Chocolate Ganache: In medium saucepan over medium heat, bring milk to a boil. Add chocolate chips; remove from heat and stir until melted and smooth. Stir in butter and chopped peanuts. Let cool.
To Assemble Cake: Remove waxed paper from sponge cake; cut cake into three 12 by 5 1/2 inch pieces. Spread half the Peanut Butter Cream over one third, piling it high and smoothing with rubber spatula. Top with a second piece of sponge cake and spread with half of the Chocolate Ganache. Top with remaining third of sponge nut Butter Cream. Refrigerate cake until ready to serve; let cake stand at room temperature for 20 to 30 minutes before serving.
To Make Chocolate Sheet to fit top of cake, cut a rectangle of waxed paper the same size as top layer of cake; place on cookie sheet. Evenly brush a thick layer of the remaining ganache mixture over waxed paper; chill until firm. Just before serving, carefully remove chocolate-coated waxed paper from cookie sheet; invert on top of cake. Gently peel off waxed paper. Trim edges with small, sharp knife if necessary. Or, if desired, simply cover entire top of cake with chocolate curls. Makes about 24 servings.
NOTE: To grind almonds, place in bowl of food processor and pulse on and off until nuts are pulverized and fluffy. Do not overprocess, as nuts will turn to a paste. I prefer a nut grinder.