For the candied lemon peel: Cut the lemons into wheels about 1/4-inch-thick and remove the peel from the fruit, keeping the peels intact. Cut the peels in half into long strips. Bring 4 cups cold water and the lemon peels to a boil in a small saucepot. As soon as the peels come to a boil, drain the water from the peels. Repeat this process three times with fresh cold water to remove the bitterness from the peels. Drain the peels and set them aside.
Combine the granulated sugar with 2 cups water in a small saucepot to make a simple syrup. Bring the syrup to a boil, stirring to dissolve the sugar. Reduce the heat to low and stir in the lemon peels. Simmer the peels until the white pith is translucent, about 40 minutes. Cool the peels in the syrup and then drain, saving the syrup for another purpose (lemon simple syrup is great in a lemon drop martini). Lay the peels on a mesh cooling rack to dry, about 2 hours. Store them packed in granulated sugar in an airtight container at room temperature.
For the lemon curd: Remove the zest from the lemons (without the bitter white pith) with a carrot peeler. Pulse the zest with the granulated sugar in a food processor until the zest has been finely minced into the sugar. Cream the butter with the sugar and zest at medium speed in a stand mixer fitted with the whisk attachment. Crack the eggs into a small bowl to ensure there are no shells, then add the eggs one at a time to the mixer until combined. Add the lemon juice and salt and blend until combined. Place the mixture into a medium saucepot. Cook over low heat, stirring constantly, until thickened, about 10 minutes. The lemon curd is ready when it reaches 170 degrees F. Transfer the lemon curd to a metal bowl and cool the bowl in an ice water bath, then cover with plastic wrap pressed against its surface and refrigerate until ready to use.
For the limoncello dip: Bring the limoncello and 2 cups water to a simmer in a medium saucepot set over medium heat. Allow the mixture to simmer for 4 minutes to cook off the alcohol in the limoncello. Remove the mixture from the heat and allow it to cool.
For the ricotta filling: Add the ricotta, confectioners' sugar, lemon zest and limoncello to a bowl. Mix to combine. Set aside at room temperature.
For the whipped cream topping: Whip the cream and granulated sugar together in a stand mixer fitted with a whisk attachment. Whisk until soft peaks are formed, then hold for the assembly of the torta. Refrigerate until ready to use.
Dip the ladyfingers halfway into the limoncello dip and line a 9-by-13-inch pan with the soaked ladyfingers. Once the bottom is covered, spread the ricotta mixture over the top evenly with an offset spatula. Place a second row of dipped ladyfingers on top of the ricotta mixture. Spread the lemon curd on top of the ladyfingers with the spatula. Place the third and final layer of dipped ladyfingers on top of the lemon curd. Spread the whipped cream topping over the ladyfingers. Refrigerate overnight. Serve well chilled, garnishing slices with candied lemon peel.
Portion the Limoncello Torta into 6 equal pieces by cutting down the middle lengthwise and then into thirds across. It is best to use two spatulas to carefully pry out the first piece from the pan.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Dough Pizzeria Napoletana, San Antonio, TX