Finely crumble the ladyfingers or coffee biscuits until they have a flour-like consistency. You can use a mixer or put them in a bag and crush them with a rolling pin.
Preparation of the compound:
In a large bowl, combine the creamy mascarpone with the sugar (if you want extra sweetness) and mix until smooth.
Add the cold espresso and, if you like, the coffee liqueur or rum . Stir well to combine the ingredients.
Incorporation of cookies:
Pour the crushed biscuits into the mascarpone cream and mix until you get a smooth and moldable dough. If the dough is too soft, add more crushed biscuits; if too hard, a drop of coffee.
Formation of truffles:
With slightly damp hands, take small amounts of dough and form into walnut-sized balls.
Cocoa coating:
Roll each ball in the bitter cocoa powder , making sure it is completely covered. This will add a nice bitter contrast to the sweetness of the truffles.
Cooling:
Arrange the truffles on a tray lined with baking paper and leave them to rest in the refrigerator for at least 30 minutes, so that they firm up and the flavors blend together.
