Add ice cubes and water to a measuring cup. Cut the butter into ¼" cubes. Place both items in the refrigerator until ready to use.

In a stand mixer bowl, add the flour and salt. Mix using the paddle attachment on the lowest speed for about 10 seconds. Add the chilled butter to the bowl. Mix on low speed until the flour and butter resemble wet sand, about 60 to 70 seconds.

Gradually add 1 tablespoon of ice-cold water to the bowl and mix until dough looks lumpy and hydrated.

Press the dough into a 1” thick round disc, wrap it, and refrigerate for at least 4 hours.

Remove the dough and roll it into a 14-inch circle, slightly less than ¼" thick.

Place the rolled-out dough into a 9-inch pie dish and trim the excess, then freeze for 20 minutes.

Preheat the oven to 375°F (190°C) and bake the crust with weights for 20 minutes, then remove weights and continue baking until golden brown.

Cut the bananas into ¼" slices and layer them in the pie shell.

In a small bowl, whisk together sugar and cornstarch and set aside. In a medium bowl, whisk together the whole eggs and yolk.

Heat the milk, rum, and vanilla bean until it reaches 180 to 185ºF. Turn off the heat.

Temper the eggs by slowly whisking in the hot milk mixture, then whisk it back into the milk.

Cook the mixture until thickened, then whisk in the softened butter.

Strain the custard into the pie shell and smooth it out. Chill in the refrigerator for at least 3 hours.

Make the whipped cream and spread it over the pie. Optionally, use a piping bag for decoration.

Sprinkle almond slices on top if desired. Refrigerate until ready to serve.