Sprinkle coconut flakes in a 9-inch glass pie plate. Toast coconut in the oven for 9 minutes, stirring every 3 minutes, until golden brown. Keep the oven on. Cool coconut and set aside 1 tablespoon of toasted coconut for garnish later.
In the bowl of a food processor, combine remaining toasted coconut with graham crackers. Pulse until fine crumbs form, about 15 one-second pulses. Transfer crumbs to a medium bowl. Stir in sugar, then melted butter until the mixture resembles wet sand.
Transfer mixture to pie plate and use the bottom of a measuring cup to press the mixture into the bottom and 1-1/2 inches up the sides of the plate.
Bake the crust at 325° F for 15 to 20 minutes or until fragrant and starting to brown. Cool completely and prepare the filling.
Coconut Cream Filling
In a medium saucepan over medium heat, combine coconut milk, whole milk, 1/3 cup sugar and salt. Stir in the coconut flakes. Bring mixture to a simmer, then take it off the heat. Keep the stove on.
Quickly, in a separate bowl, whisk together the egg yolks and remaining 1/3 cup sugar. First, whisk the flour into the warm milk mixture, then keep whisking while slowly add the egg mixture to the saucepan. Remember to constantly stir to prevent the eggs from scrambling. Return saucepan to medium heat and continue whisking until mixture thickens, about 1 to 2 minutes.
Take the saucepan off the heat, stir in vanilla and butter pieces.
Pour the coconut cream filling into the cooled crust. Cover the pie with plastic wrap, pressing it down to touch the filling. Chill for at least 3 hours.
When ready to serve, remove plastic wrap, garnish with whipped cream and remaining tablespoon of toasted coconut.
Notes
Unsweetened shredded coconut is highly recommended for the filling. It is shredded into finer pieces, which can be left in the filling for the most coconut flavor. It also balances out the sweetness from the sugar and crust.Full-fat coconut milk from the can is a must in order for the filling to set properly and achieve a creamy custard texture. Do not use light or low-fat varieties.Store pie loosely covered with plastic wrap or aluminum foil. Keep in the refrigerator for up to 5 days.Freeze pie for up to 3 months. Wrap the pie in two layers of plastic wrap to prevent freezer burn. Defrost in the refrigerator before adding the whipped cream topping and serving.