Mix your coffee and spiced rum together.
Break your sponge fingers to a size that fit your glasses, then roll in the coffee and rum mixture for 2 seconds on each side.
Place into your glasses or trifle dishes so that all of the base is covered.
Spread over half of your cream and mascarpone mixture and level out.
Grate over a layer of dark chocolate, use the zester side of your grater to ensure a very fine layer.
Repeat with another layer of sponge fingers, cream mixture and grated chocolate,
Sift over a layer of cocoa powder.
To create chocolate rolls, melt your dark chocolate either in a bain marie or in blasts of 10-20 seconds in a heatproof dish in a microwave, stirring in between, then mix in your butter.
Spread your melted chocolate out in a thin layer on a chopping board or on the back of a baking tray, allow to cool but not set fully hard.
Take a knife and push the blade into the chocolate, push it away from you in a circular motion to create a curl, see the video in the blog for a demonstration.
Decorate your tiramisu cups with your chocolate curls.
Refrigerate your Tiramisu Cups for at least 4 hours, but preferably overnight for 12 hours.