(Pie Dough recipe from Cook's Illustrated, Chocolate Pastry Cream recipe from King Arthur Flour)
Step 1: Chocolate Pastry Cream
3 cups whole milk
1/2 cup sugar
1/4 tsp. salt
1/4 cup cornstarch
1 Tbps. all-purpose flour
4 large egg yolks
2 tsp. vanilla extract
1/4 cup (1/2 stick) butter
1 cup (6 ounces) good quality milk chocolate, finely chopped
For the Pastry Cream:
In a medium-sized saucepan, stir together 2 1/2 cups of the milk, the sugar, and salt. Bring to a simmer over medium heat, stirring to disolve the sugar.
Meanwhile, whisk the cornstarch, flour, and egg yolks with the remaining 1/2 cup milk.
Whisk some of the hot milk mixture with the egg yolks to temper them. This keeps the yolks from turning to scrambled eggs when you add them to the simmering milk.
Pour the egg/milk mixture back into the simmering milk. Doing this through a strainer will help prevent lumps later. Bring to a boil, stirring constantly with a whisk, until the mixture thickens.
Remove from the heat and strain through a fine sieve into a bowl that contains the butter, chocolate, and vanilla extract. Mix until everything is incorporated, cover with a piece of plastic wrap directly on the surface of the pastry cream to prevent a skin forming. Refrigerate until cool, and up to 5 days.
Step 2: Pie Dough for Custard Pies
1 recipe single crust pie dough for a 9-inch pie (my go-to recipe is Cook's Illustrated's Foolproof Pie Dough)
1/4 to 1/2 cup graham cracker crumbs (from about 3 whole crackers)
1 large egg (optional, if using dough scraps to bake cutout pie toppers), blended
Roll out crust into a 12-inch circle using graham cracker crumbs instead of flour. Fit into a 9-inch pie plate, trim dough as needed, leaving a 1-inch overhang of dough around the sides of pan. Fold dough under itself to create a sturdy rim and flute the edges. Refrigerate pie dough until chilled, at least 30 minutes.
Preheat oven to 375 degrees F setting the oven rack on the second lowest level. Remove dough from refrigerator and place on a baking sheet. Line inside with foil (I like to use 2 pieces one vertical, one horizontal, Reynold's Non-Stick Foil, non-stick side down, in order to ensure none of the sides are exposed). Fill with pie weights and bake for half an hour. After 30 minutes remove foil and pie weights, rotate baking pan front to back, return to oven and bake another 10-12 minutes until crust is golden brown and completely cooked. Let cool to room temperature. Shell can be stored, unfilled, covered with plastic wrap, up to 1 day.
If desired, use extra dough scraps to bake pie dough cutouts. Cut into desired shapes, refrigerate until chilled, brush with egg wash and bake at 350 for 10-15 minutes until golden brown. Let cool.
Step 3: Assembling the Pie
Chilled chocolate pastry cream
Baked pie shell
2-3 ripe bananas, peeled and thinly sliced
Remove pastry cream from refrigerator, and using a spatula, spoon a layer covering the bottom of the pie shell. Top with a layer of bananas. Cover bananas with another layer of chocolate pastry cream and top with remaining banana slices. Add one final layer of chocolate pastry cream smoothing over the bananas and to the top of the pie shell.
If using baked pie dough cutouts, place them decoratively on the pie. Cover with plastic wrap and return to the refrigerator until well chilled, about 2 hours. Serve with whipped cream, if desired.