Place a baking sheet in the oven and preheat to 350°F.
For the crust, mix the graham cracker crumbs and butter in a bowl. Press the crumbs evenly over the bottom and sides of a 9-inch pie pan. Bake for 8 minutes. Let cool.
Chop the chocolate, then grind in food processor or blender. Set aside.
Place the milk in top of a double boiler or heatproof bowl. Sprinkle with gelatin. Let stand 5 minutes to soften.
Set the top of the double broiler or heatproof bowl over hot water. Add 1/3 cup of sugar, the chocolate and egg yolks. Stir until dissolved. Add the vanilla extract.
Set the top of the double boiler in a bowl of ice and stir until mixture reaches room temperature Remove from the ice and set aside.
Whip the cream lightly. Set aside. With electric mixer, beat egg whites and salt until soft peaks form. Add the remaining sugar and beat only enough to blend.
Fold a dollop of egg whites into the chocolate mixture, then pour back into the whites and fold in gently.
Fold in the whipped cream and pour into the pastry crust. Put in freezer until just set, about 5 minutes. If the center sinks, fill with any remaining mixture. Chill for 3-4 hours. Decorate with whipped cream and chocolate curls. Serve cold.