Assembly the cake on a large serving plate
(1) With a knife, spread four slices of bread with half of the filling.
(2) Place four slices of bread on top.
(3) Spread with the remaining filling.
(4) Place the last slices of bread on top.
(5) Use the “icing” mixture to spread over the top and all sides.
(6) Cover completely with plastic wrap.
Let it rest overnight in the fridge.