Crush the Ladyfingers: Place ladyfingers in a food processor and pulse into fine crumbs. Alternatively, crush them in a sealed bag using a rolling pin.
Make the Filling: In a large bowl, beat mascarpone, powdered sugar, espresso, coffee liqueur, and vanilla until smooth and creamy.
Combine: Stir in the crushed ladyfingers until a soft, uniform dough forms. It should hold together when rolled.
Chill the Mixture: Cover the bowl and refrigerate for 30–45 minutes, until firm enough to shape.
Shape and Coat: Scoop tablespoon-sized portions, roll into balls, then dip in melted white chocolate. Place on parchment-lined trays and dust with cocoa powder. Chill until set.