Step 1

Make the orange curd: Place 1/2 cup thawed orange juice concentrate, 1/3 cup granulated sugar, and 4 large egg yolks in a medium saucepan and whisk to combine. Heat over medium-low heat, stirring constantly with a silicone spatula, until the mixture thickens enough to coat the spatula, 4 to 6 minutes. Stir in 4 tablespoons unsalted butter until melted and fully combined.

Step 2

Strain the mixture through a fine-mesh strainer into wide, shallow dish (like a casserole dish) – this will help it cool quickly. Press a sheet of plastic wrap directly onto the curd and refrigerate until fully set, at least 45 minutes. Meanwhile, make the crust.

Step 3

Make the crust: Arrange a rack in the middle of the oven and heat the oven to 350°F. Melt 1 stick unsalted butter in the microwave or on the stovetop. Place 2 1/2 cups cornflake cereal in the bowl of a food processor fitted with the blade attachment and pulse until fine crumbs form. Add the melted butter and a pinch fine salt and pulse to combine. The mixture should hold together when pressed.

Step 4

Transfer the mixture into a 9-inch pie plate. Press the crumbs evenly into the bottom and the sides. Bake until golden-brown, 10 to 12 minutes. Place on a wire rack and let cool completely.

Step 5

Make the filling: When the curd is cool, place 1/3 cup granulated sugar and 3 tablespoons cornstarch in a medium heatproof bowl and whisk to combine. Add 2 large egg yolks and whisk to combine.

Step 6

Place 1 1/4 cups whole milk and 1/2 teaspoon fine salt in a medium saucepan and bring to a simmer over medium heat. While whisking constantly, pour about 1/4 of the warm milk into the egg yolk mixture in a slow, steady stream. Pour the egg yolk mixture into the saucepan with the milk and heat over medium-low heat, stirring constantly with a silicone spatula, until the mixture comes to boil – a few large bubbles in the center of the pot. Stir in 2 teaspoons vanilla extract and 1 tablespoon butter and mix until fully combined.

Step 7

Add the chilled orange curd and stir to combine. Strain the custard through a fine-mesh strainer into the cooled pie crust. Smooth into an even layer, and press a sheet of plastic wrap directly onto the surface. Refrigerate until well-chilled, at least 2 hours and up to 24 hours.

Step 8

Place 1 cup cold heavy cream, 1/3 cup powdered sugar, and the remaining 1 teaspoon vanilla extract in a medium bowl and whisk to medium peaks. Spread the whipped cream evenly over the pie, leaving about 1/2 inch of custard uncovered around the edges. Garnish with the finely grated zest of 1 medium orange. Keep refrigerated until ready to serve.