Quickly dip ladyfingers in the brewed espresso. Layer ladyfingers across the bottom of the pan. Layer mascarpone filling on top of the espresso ladyfingers. Layer the wine soaked berries on top of the masacrpone filling. Repeat.
Chill the prepared blackberry tiramisu icebox cake in the fridge for about 2 hours to set the top. Cover with plastic wrap and chill an additional 6 hrs. Before serving, top with a dusting of powdered cocoa and more fresh blackberries.