Whip 1/3 cup sugar and egg yolks together for 2 minutes, until they are light yellow in color and have tripled their volume. Place in a heat-proof bowl. Place bowl on top of a shallow pan with simmering water. Continue whisking continuously for five minutes or until the mixture reaches 150˚. Let the mixture cool for 10 minutes
In a large mixing bowl, combine the heavy cream with the mascarpone. Whip until soft peaks are formed. Gently fold the egg mixture in.
Blend the remaining 2 tbsp sugar, rum and SOOC Espresso balsamic with the espresso or coffee until the sugar is dissolved.
Pouring 8 cookies per layer, dip each cookie one at a time. Place the lady fingers, in a single, overlapping layer with some space between them, on the bottom of a 2- to 3-quart dish. Spread 1/3 of the mascarpone over the cookies.
Cover the tiramisu and place it in the refrigerator for at least six hours. Just before serving, sprinkle cocoa powder or shave chocolate over the top.