Start by whisking the mascarpone, cream, sugar, and vanilla extract until smooth.
In another bowl, mix the coffee and rum.
Dip the gingerbread biscuits into the coffee mixture, one at a time, until they are evenly coated.
Arrange the biscuits in the bottom of a glass or ceramic dish.
Spread half of the mascarpone mixture over the biscuits, and sprinkle with half of the chocolate shavings.
Repeat the layers, and refrigerate for at least 2 hours before serving.
Enjoy your Christmas gingerbread tiramisu!