The behavioral questioning approach is solid, but I've found even that has limits when candidates come prepared with rehearsed scenarios. What's been more revealing for me is asking them to explain gaps or inconsistencies in their timeline on the spot - genuine candidates can usually walk through their career progression naturally, while fake profiles tend to stumble on those unscripted details.
The telecommunications space seems particularly vulnerable to this - we've had several instances where candidates claimed network engineering experience but couldn't walk through basic troubleshooting scenarios when pressed. I've found that asking them to describe a specific outage they handled or explain their role in a particular infrastructure project usually separates the real candidates from the questionable ones pretty quickly. The structured approach definitely helps, though I agree it's a balancing act since you don't want to scare off legitimate talent with what feels like an interrogation.