Get ready to indulge in this delightful dessert by following these easy steps:

1. Prepare the Coffee: Brew a strong cup of coffee and allow it to cool to room temperature. Stir in ¼ cup of granulated sugar and ¼ cup of lemon juice until dissolved.

2. Make the Lemon Mixture: In a mixing bowl, combine the remaining lemon juice, lemon zest, and ¾ cup of granulated sugar. Stir well to combine.

3. Mix the Mascarpone: In another bowl, whisk the mascarpone cheese until smooth and creamy. Add in the lemon mixture and gently fold until well incorporated.

4. Whip the Cream: In a separate bowl, whip the heavy cream with vanilla extract until stiff peaks form. Carefully fold this whipped cream into the mascarpone mixture. Ensure not to deflate the cream.

5. Soak the Ladyfingers: Briefly dip each ladyfinger into the coffee mixture. Ensure they are soaked but not soggy.

6. Layer the Cake: In a baking dish or a deep serving platter, arrange a single layer of soaked ladyfingers at the bottom. Spread a layer of the mascarpone mixture over them. Repeat this process, layering until all ingredients are used, finishing with the mascarpone layer on top.

7. Chill: Cover the cake with plastic wrap and refrigerate for at least 4 hours, or preferably overnight. This allows the flavors to meld perfectly.

8. Serve: When ready to serve, dust the top generously with cocoa powder. Garnish with additional lemon zest for a refreshing touch.