The best interview technique I've used (in addition to all the relevant skill/tech part) was "Tell me about a hobby you're into in your free time?" And then ask

The best interview technique I've used (in addition to all the relevant skill/tech part) was "Tell me about a hobby you're into in your free time?" And then ask follow-up questions. I think it worked because (1) anybody can talk about their favorite hobby, (2) it relaxes people, as they're the expert, and (3) it demonstrates how much of a self-starter / -learner they are. The best hire I ever made was because the person worked on their motorcycle and explained the mechanic stuff they'd done during the interview. I was comparing the candidates afterwards in my head, and was hard pressed to imagine someone who worked on engines for fun in their free time, and wouldn't also be able to do this job. Hired that person, and they were amazing!