Mix sugar, flour, sale, and cocoa in a medium saucepan.
Stir in milk and egg yolks.
Cook over low heat until thick, stir often.
Remove from heat and add butter and vanilla.
Pour into cooked pie shell.
Beat egg whites to make meringue.
Top pie with meringue.
Refrigerate.
Stir in milk and egg yolks.
Cook over low heat until thick, stir often.
Remove from heat and add butter and vanilla.
Pour into cooked pie shell.
Beat egg whites to make meringue.
Top pie with meringue.
Refrigerate.
