For the Hoosier mama s'more pie: Combine 3/4 cup (178mL or 181g) of the milk and 1/2 cup (119mL or 116g) of the cream in a small, heavy saucepan. Bring to a boil over medium-high heat, stirring occasionally so the milk does not scorch on the bottom of the pan.
Meanwhile, whisk the remaining 1/4 cup (59mL or 60g) of the milk into the cornstarch to make a slurry. Set aside.
Place the egg into a medium, deep heatproof bowl. Whisk in the sugar until well combined. Slowly pour in the slurry and whisk until smooth. Gradually whisk in the hot milk mixture, stirring until well combined.
Pour the mixture back into the saucepan and cook over medium heat, whisking constantly, until it starts to thicken and just begins to boil. Whisk at a boil for 2 more minutes. Remove the saucepan from the heat and add the chocolate and butter. Whisk until both are melted and well incorporated. Whisk in the vanilla paste and salt.
Pour the pastry cream through a fine-mesh strainer into a heatproof bowl. Place a piece of plastic wrap directly onto the surface of the pastry cream and gently smooth with your fingers. This will prevent a skin from forming on the top of the pastry cream. Chill in the refrigerator until it is firm, about 2 hours. You can speed this process by placing the bowl of pastry cream over an ice-water bath.
For the chocolate ganache: Place the bittersweet chocolate in a small, heatproof bowl. Bring the cream to a boil over medium heat. Pour the cream over the chocolate. Let stand for 30 seconds. Wisk the cream and chocolate until smooth.
Spread the ganache in the Graham Cracker Crumb Crust Shell and place the shell in the refrigerator until the ganache is set, about 30 minutes.
Remove the chocolate pastry cream from the refrigerator and transfer to the bowl of a stand mixer fitted with the whisk attachment. Whip on Medium until it is light and fluffy. Remove from the stand mixer and set aside. Thoroughly wash the stand mixer bowl.
In the bowl of the stand mixer still fitted with the whisk attachment, whip the remaining 1/2 cup (119mL or 116g) of the cream to soft peaks. Gently fold the whipped cream into the pastry cream.
Remove the prepared pie shell from the refrigerator. Spoon the pastry cream into the shell, over the ganache. Gently smooth the top of the pie with an offset spatula, making sure the pastry cream touches the edge of the pie shell. Chill in the refrigerator until the pastry cream is set, about 1 hour.
For the creamy meringue: Fill a 1-quart (948-mL) saucepan halfway with water and bring to a simmer over medium-high heat.
Combine the egg whites and granulated sugar in a medium stainless steel bowl and whisk to incorporate the sugar and break up the whites. Rest the bowl on top of the pot of simmering water and whisk constantly, until the egg whites reach 165 degrees F on an instant-read thermometer.
Pour into the bowl of a stand mixer and whip on high until the mixture is lukewarm.
Pour it directly onto the center of the pie and, with the back of a serving spoon, spread it out from the center in concentric circles. Toast with a butane torch. Be sure to get a few spots "extra toasty," as if it got scorched in the campfire! The finished pie can be served immediately.
In a medium bowl, combine the dry ingredients (graham cracker crumbs and sugar).
Pour in the melted butter.
Rub the butter into the crumbs with your fingers, until the mixture holds together when a small amount is squeezed in the palm of your hand.
Pre-heat oven at 350 degrees F.
Lightly brush a 9-inch (22.5-cm) pie tin with melted butter.
Place the crumb mixture in the pie tin and press it firmly into an even layer across the bottom and up the side of the pie tin.
Place a second 9-inch (22.5-cm) disposable aluminum pie tin directly on top of the crumb mixture. Press firmly on the bottom of the pie tin, working your way out from the center so that you smooth the crumbs from the center of the pie tin toward the side.
Work your way around the tin, starting where the bottom of the tin meets the side and working your way up. Some of the crumb mixture will be pushed up over the edge of the first tin. Press it back down around the top of the disposable pie tin. This will form a rim.
Remove the second pie tin and fill in any bare or thin spots. Use the second pie tin to tamp down your patches.
Place the finished shell on a baking sheet and bake for 6 minutes. Do not overbake. Allow the shell to cool slightly before filling.
The unbaked pie shell can be stored in the freezer, tightly wrapped, for up to 2 weeks, or in the refrigerator for up to 3 days. The baked shell can be stored at room temperature for up to 2 daysdo not refrigerate. We've found that crumb shells freeze
The chocolate pastry cream can be made up to 1 day in advance. The finished pie can be stored in the refrigerator for 2 to 3 days. You can also use homemade or store-bought gingersnaps to make this shell. If you are using homemade, be sure to let them dry out a bit before grinding them into crumbs.
Propane gas torches are highly flammable and should be kept away from heat, open flame and prolonged exposure to sunlight. They should be used only in well-ventilated areas. Follow torch manufacturer's instructions for use.
Adapted from "The Hoosier Mama Book of Pie" by Paula Haney © Agate Midway 2013. Reprinted with permission of Paula Haney. All rights reserved.