(I confess that this particular one is in a purchased crust...I made three pies today because it's pie night, and I just didn't feel like doing a 4th!)
1 envelope unflavored gelatin
1/2 c cold water
1/2 c sugar
1/4 c cocoa
1 can evaporated milk
1 Tbs vanilla
graham cracker or cookie crumb pie crust
In 1 qt saucepan, soften gelatin in the water. Stir in sugar and cocoa.
Stir over medium heat until gelatin and sugar are completely dissolved (about 5 minutes). Do NOT let it boil.
Take off heat, and stir in 1 c of the evaporated milk, then put in a medium size (2qt) bowl and chill until firm (at least 1 hour).
Remove from fridge, and slowly mix in the rest of the can of milk (about 2/3 c) plus the vanilla. Beat on low speed until the mixture is broken up, then beat on high speed until the mixture fills the bowl.
Allow to rest for a few minutes, then put in the pie crust and chill until firm--about 1 hour.