Chocolate Cream Pie

Ingredients:

Prepared chocolate pie crust
For filling:
2/3 cup sugar
1/4 cup cornstarch
1/2 teaspoon salt
4 large egg yolks
3cups whole milk
5 oz fine-quality bittersweet chocolate (not unsweetened), melted
2 oz unsweetened chocolate, melted
2 tablespoons  butter, softened
1 teaspoon vanilla
For topping
3/4 cup chilled heavy cream
1 tablespoon sugar
Directions for filling:
1. Whisk together sugar, cornstarch, salt, and yolks in a 3-quart heavy saucepan until combined well, then add milk in a stream, whisking.   Bring to a boil over moderate heat, whisking, then reduce heat and simmer, whisking, 1 minute (filling will be thick).
2.Whisk in chocolates, butter, and vanilla. Cover surface of filling with wax paper and cool completely, about 2 hours.
3.Spoon filling into crust and chill pie, loosely covered, at least 6 hours.

Directions for topping:

1.   Just before serving, beat cream with sugar in a bowl using an electric mixer until it just holds stiff peaks, then spoon on top of pie.
Note: Pie (without topping) can be chilled up to one day.