Roughly chop the chocolate, mealt over a water bath.

Whisk together egg yolks with sugar. Incorporate the molten chocolate, as well as as mascarpone, cocoa, salt, rum, vanilla and orange zest. Gently mix together until a thick cream forms.

Put into a flat bowl, cover with cling film and freeze for 1 to 2 hours.

Using a spoon, divide the cream. Using your hands, shape into round truffles.

Dip into sprinkles or chocolate crispies. Serve chilled.