01 - Combine water, lemon juice, and sugar in a small saucepan. Heat over medium heat, stirring continuously, until the sugar fully dissolves. Remove from heat and let cool completely before using.
02 - In a large mixing bowl, whisk the cold mascarpone, heavy cream, granulated sugar, lemon zest, lemon juice, and vanilla extract until the mixture is smooth, thick, and holds soft peaks.
03 - Briefly dip each ladyfinger into the cooled lemon syrup, just a quick one-second pass on each side. Avoid soaking to prevent the layers from becoming soggy.
04 - Arrange a single layer of dipped ladyfingers in the bottom of an 8x8-inch dish, fitting them snugly without overlapping.
05 - Spread half of the lemon cream evenly over the first layer of ladyfingers using a spatula, ensuring full coverage to the edges.
06 - Place a second layer of dipped ladyfingers over the cream, maintaining the same quick-dip technique.
07 - Top with the remaining lemon cream and smooth the surface evenly with a spatula.
08 - Cover the dish tightly with plastic wrap and refrigerate for at least 4 hours, or overnight for the best texture and flavor development.
09 - Before serving, finish with a sprinkle of fresh lemon zest and optional white chocolate curls or mint leaves. Serve chilled.