6 egg yolks
1/2 cup sugar
2 Tablespoons flour
2 Tablespoons cornstarch
1/4 teaspoon salt
3 cups whole milk
1 cup heavy cream
1 1/4 cups best-quality semi-sweet chocolate chips (I like Ghiradelli)
In a medium bowl whisk together egg yolks, sugar, flour, cornstarch, and salt.
In a saucepan bring the milk and heavy cream up to a simmer. Whisk 1/2 cup of the mixture into the egg mixture, then whisk the egg-milk mixture into the saucepan, mixing thoroughly. Bring the mixture back up to a boil over medium-low heat, stirring constantly, then cook for 2 minutes longer, until the cream is thick. Remove from the heat and add the chocolate chips, whisking until they are melted. Transfer to a bowl, then cover with plastic wrap and refrigerate until cool, about 2 hours. (For pie, cool to room temperature, covered with plastic wrap, then spread into the baked pie shell, cover with plastic, and refrigerate for at least 4 hours before garnishing and serving.