This old bake-off recipe from the “Ice Box Pie” category is a Southern favorite. It’s basically a chocolate mousse in a crust.
Use a commercial refrigerated pie crust for this recipe because the crust must be blind baked, and blind-baking a homemade crust is tricky. Blind baking simply means pre-baked, and you pre-bake crusts for refrigerator pies—those that aren’t baked—so the crust won’t get soggy. Some people will also blind bake crusts for pies with a dense filling (e.g. pumpkin or sweet potato). Use a glass pie pan.
Drape the crust over a rolling pin and ease the crust into the pan without stretching it. Wet your fingers and press any cracks together. Press the crust firmly against the sides and bottom. It helps to pop it into the freezer for five minutes or so to keep it from slumping down the sides. Generously prick the crust on the bottom and sides to prevent bubbling, and line the inner edges with heavy-duty aluminum foil. Put your pan on a preheated sheet pan and bake the crust for 10 minutes at 400 with the foil, remove the foil and return to the oven for maybe five minutes to brown.
Whip a cup of heavy cream to stiff peaks, cover and chill. Melt 8 oz. chopped bittersweet chocolate (I use a glass bowl in the microwave). Stir until smooth and set aside. Add 3 eggs, ¾ cup sugar, and a couple of tablespoons of water to glass bowl. Beat with an electric mixer 5 minutes, until pale yellow and thick. Place this bowl over a smaller pot of simmering water and cook, whisking continually, until the mixture is hot through and through. Remove from heat and continue beating until cooled and fluffy. (This might take up to 10 minutes because you want some serious fluff.) Add the melted chocolate, 2 teaspoons vanilla, a stick of very soft butter, and beat until very smooth. Now carefully blend in the whipped cream, just until you have a more or less even color; don’t over-mix.
Pour mixture into the pie crust and spread evenly. Top with another half cup of whipped cream sweetened with a quarter cup powdered sugar and a teaspoon vanilla (or almond) extract. Beat ½ cup cream till soft peaks form, add the powdered sugar and vanilla and beat till stiff and smooth. Spread over the chocolate filling. Cover lightly with plastic wrap and refrigerate for at least three hours.