Instructions

  1. Combine 1/4 cup sugar, cornstarch, flour, cocoa and salt in small bowl.
  2. Blend well.
  3. Stir in 1/4 cup milk and egg yolks.
  4. In a saucepan, combine remaining 3/4 cup sugar and remaining 2 cups milk; place over medium heat and gradually bring to a boil.
  5. Remove from heat.
  6. Stir 1 cup hot milk mixture into the cocoa mixture, then return to saucepan.
  7. Bring to a boil over medium-high heat, stirring constantly.
  8. Let mixture boil for 5 minutes while continuing to stir.
  9. Remove from heat and stir in butter and vanilla.
  10. Pour into pie shell and let chill 2-3 hours before serving.
  11. Top each slice with a dollop of Cool Whip when serving.