In a mixing bowl, whisk together the mascarpone cheese, powdered sugar, and vanilla extract until smooth.

In a separate bowl, whip the heavy cream until stiff peaks form.

Gently fold the whipped cream into the mascarpone mixture until fully combined.

Stir in the limoncello until well incorporated.

In a shallow dish, combine the cooled coffee and limoncello.

Quickly dip each ladyfinger into the coffee mixture, ensuring they are soaked but not soggy.

Layer half of the soaked ladyfingers in the bottom of a 9x9 inch baking dish.

Spread half of the mascarpone cream mixture over the ladyfingers.

Repeat the layers with the remaining ladyfingers and mascarpone cream.

Cover and refrigerate for at least 4 hours, preferably overnight.

Before serving, garnish with lemon zest on top.