Repacked stock rom:http://dl.project-voodoo.org/transformer-roms/3.0.x/
2. Copy the files onto your micro sd. Unzip stock update and place the Asus folder on root of sd card.
3. Boot into recovery. install repacked stock rom. Wipe all data, cache partition and dalvik cache. Reboot the tablet let it boot up then shut it down.
4. Boot into recovery and install stock recovery. Wipe all data, cache partition and dalvik cache. And then reboot and shut down.
a.Boot into OS, there should be a notification for an update. select it and follow instuctions. Or
b.Boot into recovery(it should be stock recovery) then press up volume button within five seconds and the official update should install.
6. It should reboot automatically. When it does check about tablet info and check your apps to make sure the Super User icon is gone.
Here is another method. I have not tried it myself but I figured it might be helpful to someone: