In a large mixing bowl, whip the heavy cream until soft peaks form. Gradually add the powdered sugar and vanilla extract, continuing to whip until stiff peaks form.

In another bowl, combine the mascarpone cheese, lemon juice, and lemon zest. Gently fold the whipped cream into the mascarpone mixture until well combined.

Quickly dip each ladyfinger into the cooled coffee for about 1 second, ensuring they are soaked but not soggy.

In a 9x9 inch dish, layer half of the soaked ladyfingers on the bottom. Spread half of the lemon mascarpone mixture over the ladyfingers. If using, add a layer of lemon curd on top.

Repeat the process with the remaining ladyfingers and lemon mascarpone mixture.

Cover the dish with plastic wrap and refrigerate for at least 4 hours, or overnight for best results.

Before serving, garnish with fresh mint leaves and additional lemon zest if desired.