Chocolate Creme Pie

This was my first attempt at making a chocolate creme pie from scratch (well at least the filling) and I'd say it was a huge success!

Ingredients:
1 pre-made Oreo pie crust
Whipped cream
Pie filling
 - 1 cup of sugar
 - 3/4 cup of heavy cream
 - 3/4 cup of buttermilk
 - 3 1/2 tablespoons of cornstarch
 - Pinch of salt
 - 4 egg yolks
 - 4 ounces of Ghirardelli semisweet chocolate chips
 - 1 tablespoon of butter
 - 3/4 teaspoon vanilla extract

Directions for pie filling:
 - In a small saucepan combine sugar, heavy cream, buttermilk, cornstarch and salt. Whisk until smooth and then place over medium high heat. Bring the mixture to a boil, whisking from time to time (about 5 minutes). Continue cooking at a low boil for an additional 5 minutes while whisking constantly.

 - In a mixing bowl, beat the egg yolks lightly. Pour 1/2 cup of the hot mixture into the egg yolks and whisk thoroughly. Pour the egg yolk mixture into the saucepan and whisk over hear until thoroughly combined and very thick, 1 to 2 minutes.

 - Pour the mixture into a mixing bowl, whisk in the chocolate, butter and vanilla. Again, continue to whisk until thoroughly combined. Cover the mixture with plastic wrap that is placed directly on the surface and refrigerate until cooled to room temperature, about 35 minutes.

 - Once cooled, put mixture into pie crust and smooth the top. Refrigerate for at least 4 hours before serving.

 - Top with whipped cream and enjoy!