For the fluff, over a double boiler heat the sugar and egg whites together until extremely hot to the touch, dissolving the sugar and pasteurizing the whites. Whip in a mixer on high speed until cool. Reserve in a bowl.
Clean mixer bowl and then cream butter and confectioners sugar until smooth. Add peanut butter and mix until incorporated. Set aside at room temp.
To assemble the cake, make a sandwich with the peanut cream and pound cake. Top with the homemade fluff and serve.