Yeah, so in doing some googling, it seems the procedure is this:
1. ESC off (not sure if you hold until brake guard is off too?, I usually do.)
2. Pull it back into Sport.
3. Push brake firmly (apparently MASH it)
4. Push throttle gradually while RPM's rise (eventually hitting the kickdown switch as well, which I never did)
5. When tach stops, let off brake and keep throttle mashed.
2013 Audi S8