Chocolate Pudding Pie
adapted from Smitten Kitchen
3 tablespoons unsweetened cocoa powder
1/4 teaspoon salt
3 cups whole milk
4 ounces bittersweet chocolate (not more than 60% cacao), finely chopped
1 teaspoon pure vanilla extract
1 cup chilled heavy cream
1/4 cup powdered sugar
Make pudding filling: Whisk together cornstarch, 1/3 cup sugar, cocoa powder, and salt in a 2-quart heavy saucepan, then gradually whisk [tips alert!] in milk. Bring to a boil over medium heat, whisking constantly, then boil, whisking, two minutes (mixture will thicken). Remove from heat and whisk in chocolate and vanilla until smooth.
Pour filling into cooled shell and chill, its surface covered with plastic wrap (if you want to prevent a skin from forming), until cold, at least two hours.
Just before serving, beat cream with powdered sugar until it just holds soft peaks. Spoon onto pie.