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. 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, about five minutes. Initially, it will seem a little liquidy, but it will thicken as you beat it.
Alternatively, if you don't want to use raw egg yolks, place a heatproof mixing bowl with the egg yolks and sugar on a medium saucepan filled with 2-3 inches of simmering -- not boiling -- water and beat until the mixture thickens and about doubles in volume, approximately seven to 10 minutes. The heat will gently cook the eggs. If it starts to get too hot, lift the bowl and give it a chance to slightly cool. Remove the bowl from the heat and let it cool for about 15 minutes. Then, beat in the mascarpone, molasses and spices until light and fluffy.
Gently fold the whipped heavy cream into the mascarpone mixture until fully incorporated.
Quickly dip each ladyfinger into the cooled coffee mixture, no more than three seconds. Layer on the bottom of an 8-inch-by-8-inch baking dish. Spread half of the gingerbread-mascarpone filling on top. Repeat with the remaining ladyfingers and spread the other half of the gingerbread-mascarpone filling.
Cover with plastic wrap and refrigerate for at least six hours. Sprinkle with additional cinnamon for a garnish if desired. Enjoy!