1. Combine Dry Ingredients:
- In a medium saucepan, stir or whisk together the sugar, cornstarch, and salt.
2. Add Milk and Egg Yolks:
- Pour in the milk and egg yolks, whisking to combine.
3. Cook the Filling:
- Stir over medium heat until the mixture just barely comes to a boil and becomes thick, about 6 to 8 minutes (maybe less, maybe more; just watch it). The mixture should be thick like pudding.
4. Remove from Heat and Add Remaining Ingredients:
- The second it starts to bubble and thicken, remove it from the heat.
- Add the chopped bittersweet chocolate, vanilla extract, and butter.
- Stir until everything is beautifully combined and the chocolate and butter are melted.
5. Pour into Crust and Chill:
- Pour the hot chocolate pudding into the baked and cooled pie crust. (If there is extra, spoon it into small dishes for individual servings!)
- Place the pie in the refrigerator, uncovered, to chill for at least 4 hours. This allows the filling to set completely.
6. Serve:
- Cut the chilled pie into slices and serve with whipped cream.