(from americastestkitchen.com)


   Chocolate Cream Pie 
   Serves 8 to 10
   For the best chocolate flavor and texture, we recommend either
   Callebaut semisweet and unsweetened chocolates or Hersheys Special
   Dark and Hersheys unsweetened chocolates. Do not combine the yolks and
   sugar in advance of making the fillingthe sugar will begin to break
   down the yolks, and the finished cream will be pitted.

   Chocolate Cookie Crumb Crust
   16 Oreo cookies (with filling), broken into rough pieces, about 2½
   cups
   2 tablespoons unsalted butter, melted and cooled

   Chocolate Cream Filling
   2 1/2 cups half-and-half
   Pinch salt
   1/3 cup (2.3 ounces) sugar
   2 tablespoons cornstarch
   6 large egg yolks, room temperature, chalazae removed
   6 tablespoons cold unsalted butter, cut into 6 pieces
   6 ounces semisweet or bittersweet chocolate, finely chopped
   1 ounce unsweetened chocolate, finely chopped
   1 teaspoon vanilla extract
   3 cups Whipped Cream, whipped to soft peaks

   1. For the crust: Adjust oven rack to middle position and heat oven to
   350 degrees. In bowl of food processor fitted with steel blade,
   process cookies with fifteen 1-second pulses, then let machine run
   until crumbs are uniformly fine, about 15 seconds. (Alternatively,
   place cookies in large zipper-lock plastic bag and crush with rolling
   pin.) Transfer crumbs to medium bowl, drizzle with butter, and use
   fingers to combine until butter is evenly distributed.

   2. Pour crumbs into 9-inch Pyrex pie plate. Press crumbs evenly onto
   bottom and up sides of pie plate. Once crumbs are in place, line pan
   flush with large square of plastic wrap, and use spoon to smooth
   crumbs into curves and sides of pan. Refrigerate lined pie plate 20
   minutes to firm crumbs, then bake until crumbs are fragrant and set,
   about 10 minutes. Cool on wire rack while preparing filling.

   3. For the filling: Bring half-and-half, salt, and about 3 tablespoons
   sugar to simmer in medium saucepan over medium-high heat, stirring
   occasionally with wooden spoon to dissolve sugar. Stir together
   remaining sugar and cornstarch in small bowl. Whisk yolks thoroughly
   in medium bowl until slightly thickened, about 30 seconds. Sprinkle
   cornstarch mixture over yolks and whisk, scraping down sides of bowl,
   if necessary, until mixture is glossy and sugar has begun to dissolve,
   about 1 minute. When half-and-half reaches full simmer, drizzle about
   1/2 cup hot half-and-half over yolks, whisking constantly to temper;
   then whisk egg yolk mixture into simmering half-and-half (mixture
   should thicken in about 30 seconds). Return to simmer, whisking
   constantly, until 3 or 4 bubbles burst on surface and mixture is
   thickened and glossy, about 15 seconds longer.

   4. Off heat, whisk in butter until incorporated; add chocolates and
   whisk until melted, scraping pan bottom with rubber spatula to fully
   incorporate. Stir in vanilla, then immediately pour filling into baked
   and cooled crust. Press plastic wrap directly on surface of filling
   and refrigerate pie until filling is cold and firm, about 3 hours.

   5. Just before serving, spread or pipe whipped cream over chilled pie
   filling. Cut pie into wedges and serve.