1 Heat the oven to 350°F.
2 Make the graham cracker crust: Heat the oven to 350°F. Break the graham crackers into a few pieces and place in the bowl of a food processor. Process the crackers until there are no large chunks left. The mixture should be sandy but not powdery.
Pour the crumbs into a bowl and stir in the melted butter, sugar, and salt. The mixture should be like wet sand and clump together when pinched.
Press the crumbs firmly into the bottom and sides of a 9-inch pie plate to form a crust, using a measuring cup or glass to help you press firmly.
3 Bake the graham cracker crust: Bake for 10 to 12 minutes or until the crust has started to turn a slightly darker brown color and smells fragrant. Remove from the oven and set aside to cool completely.
4 Make the cream pie filling: Combine the sugar, egg yolks, and cornstarch in a medium saucepan. Whisk off the heat until they gain a little volume and turn a light yellow. Whisk in the milks and salt.
Place the pan over medium heat and whisk constantly until thickened, 15 to 20 minutes. (If this seems to be going really slowly, it’s ok to nudge the heat up a little.)
When the filling ready, the whisk should momentarily leave some visible trails on the surface before disappearing. Stir in the vanilla and shredded coconut.
5 Transfer to pie crust: Spread half of the cream filling mixture into the cooled graham cracker crust. Slice the bananas and layer them on top, then cover with the remaining custard. Make sure to cover all the bananas (so they don’t brown!).
Smooth the surface and press plastic wrap directly on top.
6 Refrigerate the pie at least 4 hours or up to 24 hours to set.
7 Make the whipped cream topping: When ready to serve the pie, use a stand mixer or hand mixer to whip the cream until it holds soft peaks. Whisk in the sugar, and continue beating until the cream holds a medium peak. Generously dollop the cream over the top of the chilled pie. Sprinkle the top with extra shredded coconut.
Once assembled, the pie can be kept refrigerated for a few hours before serving. (Longer than a few hours, however, and the whipped cream can start to weep. It still tastes good, but is less visually appealing!)