Preheat oven to 180oC/350oF/Gas
4. Mix the crushed ginger nuts and melted butter. Press evenly over the
base and side of a 23cm pie plate. Bake for 6 minutes. Sprinkle the
gelatin over the water and leave to soften.
Beat the egg yolks in a large mixing
bowl and set aside. In a saucepan, combine half the sugar, the corn
flour and salt. Gradually stir in the milk. Boil for 1 minute, stirring
constantly. Whisk the hot milk mixture into the yolks, pour back into
the saucepan and return to the boil, whisking. Cook, for 1 minute, still
whisking. Remove from the heat.
Pour 225 g of the custard mixture into
a bowl. Add the chopped chocolate and stir until melted. Stir in half
the rum and pour into the pie crust. Whisk the softened gelatin into the
plain custard until dissolved, then stir in the remaining rum. Set the
pan in cold water to reach room temperature.
Beat the egg whites and cream of
tartar until they peak stiffly. Add the remaining sugar gradually,
beating thoroughly after each addition. Fold the custard into the egg
whites, then spoon over the chocolate mixture in the pie crust. Chill
until set, about 2 hours. Decorate with chocolate curls.