I agree. In my experience, the best way to piss someone off who's trying to piss you off is to be completely oblivious to them. They'll escalate their behavior to try to elicit a response, but just take that as a cue that your strategy is working. Use that cue as your satisfaction toward victory. Eventually they will erupt in anger. When that moment finally comes it is glorious. Bystanders will be confused as to what you did to cause such anger, and she won't be able to explain it, while you get to play completely innocent. Protip: never be alone in a room with them. This can lead to all sort of accusations, and you can have witnesses that you never said or did anything untoward.