Process the ladyfinger biscuits until they reach a fine, sandy consistency.
In a mixing bowl, combine the mascarpone, cooled espresso, powdered sugar, and vanilla extract until smooth.
Fold the crushed biscuits into the mascarpone mixture until a thick, uniform dough forms.
Cover the bowl and refrigerate for 30 minutes to allow the moisture to absorb into the crumbs.
Scoop rounded teaspoons of the mixture and roll them into balls with your palms.
Place the balls on a parchment-lined tray and freeze for 10 minutes to firm up.
Melt your chosen chocolate in a microwave-safe bowl in 20-second intervals, stirring in between.
Dip each chilled ball into the melted chocolate, shaking off the excess, and return to the tray.
Once the chocolate coating is set, lightly dust the top of each truffle with cocoa powder.