Willards Chocolate Pie

Directions

1. 1
   Bring the milk to a simmer in a large saucepan over medium heat.
2. 2
   Vigilance is required so that the milk does not burn.
3. 3
   In the top of a double boiler (off the heat), mix the egg yolks, sugar, cocoa, cornstarch, and just enough of the water to make a smooth paste.
4. 4
   Use as little water as possible; its okay for the paste to be thick.
5. 5
   Slowly pour the milk into the egg yolk mixture while whisking continuously, then place over simmering water in the bottom of the double boiler and cook, stirring frequently, for 45 minutes, until quite thick with a puddinglike consistency.
6. 6
   Remove from the heat and stir in the butter and vanilla.
7. 7
   Pour the filling into a shallow container, lay plastic wrap directly on the surface, and chill in the refrigerator for about 1 hour, until cold.
8. 8
   Scrape the filling into the crust and refrigerate about 3 to 5 hours, until set.
9. 9
   Serve cold.