Prepare the Pie

• Preheat the Oven - Place the oven rack in the center position. Preheat to 350°F (176°C). Line a half-sheet pan with parchment paper and set aside.
• Make the Crust - Break the graham crackers into small pieces and add them to a food processor. Pulse on and off 5 times. Add the coconut flakes and process on low speed until the crackers break down into a fine crumb consistency and the coconut is chopped, about 35 to 40 seconds.
• Measure 1 ¼ cup of the crumbs into a medium bowl. Add the granulated sugar, and stir to combine. Add the melted butter, and stir until it coats the dry crumbs. The mixture should hold its shape when pressed together.
• Form the Crust - Place a 9-inch pie dish on the sheet pan lined with parchment paper. Pour the graham cracker crumb mixture inside. Using the bottom of a measuring cup, press the mixture evenly on the bottom and onto the sides. The mixture should just come up to the top but not go onto the edges. Gently using your hands, make sure the sides are packed, and the edges are even.
• Bake the Crust - Bake for 15 minutes, rotating halfway through. Cool on a wire rack for at least 10 minutes.
• Key Lime Filling - In the bowl of a stand mixer, add the softened cream cheese. Add the paddle attachment and mix on Speed 4 for 20 seconds. Use a spatula to scrape down the sides of the bowl. Add the egg yolks and mix on Speed 4 until combined, about 20 seconds. The mixture will be slightly lumpy. Scrape down the sides of the bowl and paddle.
• Add the sweetened condensed milk and mix on Speed 4 for a few seconds. Turn up to Speed 6 and mix until smooth, for about 30 seconds. Scrape the bowl and paddle down. Make sure there are no lumps in the mixture, and mix for a few more seconds as needed.
• Add the lime zest and lime juice to the mixer. Mix on Speed 2 until the juice stops splashing, about 5 seconds. Turn the mixer up to Speed 8 for about 20 seconds. Scrape the bowl and paddle with the spatula.
• Bake the Pie - Once the crust has cooled, place it onto the parchment-lined sheet pan. Pour the filling into the pie shell. Bake for 15 minutes, rotating halfway through. The filling will be slightly jiggly. Carefully transfer the pie to a cooling rack for 30 minutes before chilling it in the refrigerator.
• Transfer the pie to the refrigerator and chill until cold and the filling solidifies, about 2 ½ to 3 hours.
• Make Whipped Cream - Right before serving, make the whipped cream topping. In a stand mixer fitted with the whisk attachment, add heavy cream and powdered sugar. Alternatively, if using a hand mixer, use the whisk or beaters attachment and a large bowl. Processing times may vary.
• Whip on medium-low speed (setting 4) until the cream is frothy with bubbles on the surface, 1 minute. Increase the speed to medium-high (setting 8), and whip until a fluffy, smooth consistency is reached, about 75 seconds for soft peaks. Continue to beat in 5-second intervals until stiff peaks form. Be careful, the texture will change quickly. Transfer the cream to a piping bag fitted with a star tip and make a design on top of the pie.
• To Serve - Sprinkle with lime zest or slices of lime if desired. Refrigerate the pie until ready to serve.