1First, prepare the lemon curd. Add the eggs, egg yolks, sugar, and cream to a bowl and whisk to combine.
2Pour the lemon juice into a pan and bring it to a simmer.
3Add a little bit of the hot lemon juice to the egg mixture while whisking to temper the eggs.
4Pour the egg mixture into the pan with the remaining lemon juice.
5Cook over medium heat, whisking constantly, until the curd thickens.
6Pass the lemon curd through a fine-mesh strainer into a clean bowl.
7Stir in the butter until melted.
8Stir in the heavy cream and vanilla extract.
9Let it cool completely, then refrigerate until needed.
10To make the mascarpone mixture, combine the egg yolks, lemon zest, and sugar in a bowl and whisk until pale and creamy.
11Add the mascarpone cheese and whisk until smooth.
12In a separate bowl, whisk the egg whites until stiff peaks form.
13Gently fold the egg whites into the mascarpone mixture until just combined.
14To prepare the limoncello soak, combine limoncello, lemon juice, and water in a shallow dish.
15Briefly dip each ladyfinger into the limoncello soak, ensuring they are coated but not soggy. Place a single layer of soaked ladyfingers at the bottom of a serving dish.
16Spread half of the mascarpone cream over the ladyfingers.
17Add another layer of soaked ladyfingers.
18Spread the remaining mascarpone cream over the second layer of ladyfingers.
19Garnish with lemon slices and mint leaves.
20Chill in the refrigerator for at least 4 hours, or preferably overnight, before serving.