First Step: Prepare Dough and Oven Remove refrigerated pie dough from the fridge and thaw on the counter for about 10 minutes. Alternatively, chill the dough for 30 minutes beforehand to help achieve a flakier texture. Preheat your oven to 425°F (218°C) to get it ready for baking the cannoli shells.

Second Step: Cut and Shape Cannoli Shells On a lightly floured surface, unroll one pie dough circle and use a 4½-inch cookie cutter or bowl to cut four round circles; repeat with the second dough circle for a total of eight. Whisk together the egg and water to make an egg wash. Wrap each dough circle securely around a cannoli form, sealing edges with the egg wash. Freeze the wrapped forms for 10 minutes to help the dough hold its shape during baking.

Third Step: Bake Cannoli Shells Place the wrapped cannoli forms on a parchment-lined baking sheet. Bake in the preheated oven for 10 to 12 minutes, or until the shells turn golden brown and crisp. Remove from the oven and cool for 10 minutes before carefully sliding off the cannoli forms. Let shells cool completely on a wire rack to preserve crunchiness.

Fourth Step: Prepare Lemon Meringue Filling In a mixing bowl, stir together lemon curd and marshmallow fluff until smooth. Gently fold in thawed whipped topping and fresh lemon zest if using. Refrigerate the filling for at least 30 minutes to firm up and blend the flavors thoroughly.

Final Step: Fill and Garnish Cannoli Only just before serving, pipe the lemon meringue filling into cooled cannoli shells from both ends to evenly distribute. Dust each assembled cannoli lightly with powdered sugar. Optionally, add extra lemon zest or thin lemon slices for a fresh decorative touch. Enjoy this bright, creamy, and crisp take on traditional lemon meringue pie in an irresistible cannoli form.