ICACLS (Make Permissions On All Files)

Ive been trying to figure out a way to use the ICACLS command to give permissions to a test user and have them apply to all files in the directory. I know I can use a wild card but that only effects files in the folder at the time the command is executed. I have also tried using /inheritance:e as one of the arguments but it still doesnt seem to work. Can someone give me an example of how I would give the user 'Admin' full control of the directory 'c:perm test' without a wildcard. (Including all files in that dir)