Preparation Steps

• Preheat the oven to 350°F (175°C). Line a 9x13-inch baking pan with parchment paper, leaving an overhang for easy removal.
• Make the crust: In a bowl, combine 1.5 cups all-purpose flour, 0.5 cup powdered sugar and 0.25 teaspoon salt. Stir in 0.5 cup melted unsalted butter until the mixture comes together.
• Press the crust mixture evenly into the bottom of the prepared pan. Use the bottom of a measuring cup to compact it firmly.
• Bake the crust for 15 to 18 minutes, or until lightly golden around the edges. Remove from the oven and reduce oven temperature to 325°F (160°C).
• Prepare the filling: In a large bowl, whisk together 1.5 cups granulated sugar and 2 tablespoons cornstarch. Add 4 eggs and whisk until smooth. Stir in 0.75 cup fresh lemon juice, 2 tablespoons lemon zest, 0.5 cup heavy cream and 1 teaspoon vanilla extract until fully combined.
• Pour the lemon filling evenly over the warm crust and return the pan to the oven.
• Bake at 325°F (160°C) for 20 to 25 minutes, or until the filling is set but still slightly jiggly in the center. Do not overbake to preserve a creamy texture.
• Remove from the oven and let cool to room temperature, then refrigerate for at least 2 hours (or overnight) to fully set.
• Lift the chilled lemon slab from the pan using the parchment overhang. Dust the top with 0.25 cup powdered sugar, cut into 16 squares and serve chilled.