In a small bowl, mix together the espresso or coffee, white sugar and dark rum until the sugar dissolves. Set aside to cool.
In a large mixing bowl, beat the heavy cream until stiff peaks form. A hand or stand mixer works well here. Set aside.
In a separate mixing bowl, beat together the egg yolks, mascarpone, white sugar, molasses, cinnamon, ginger, cloves and allspice on medium speed until light and fluffy and no lumps remain.
Gently fold the whipped heavy cream into the mascarpone mixture until fully incorporated. It will look nice and fluffy like so.
Dip ladyfingers into coffee mixture. Layer on the bottom of a baking dish. Spread half the mascarpone filling on top. Repeat with the remaining ladyfingers and mascarpone. Refrigerate.