Cream butter and sugar well.
Sift flour once, then add cocoa, baking powder, salt and then sift again.
Alternate additions of milk, egg and flour.
Mix and pour into greased and floured tube pan.
Bake at 325º for approx. 1 1/2hours. Check for doneness with wooden skewer.
Mix sugar, salt and cocoa well.
Add milk and butter. Bring to a quick boil, stirring constantly.
Boil hard without stirring for 3- 4 minutes. (in my Grandmother's notes, she did it for exactly 4 min.)
Remove from burner, add vanilla.
Let sit awhile to cool or beat constantly until spreading consistency.
If too hard, put in a few drops at a time of evaporated milk.
If too soft, use enough powdered sugar to firm up (wish that applied to our bodies as well!).