How to interview a candidate for a university teaching position?
You'll want to ask some standard questions that any experienced educator would ask a potential teacher:


Request to see a model lesson. It doesn't have to be a full lecture, just something to see their style. Ideally the entire committee should be there for this part.
Ask to see a university-level lesson plan of their creation.
Ask how they would approach creating a semester-long curriculum for an advanced "special topics" course. I suggest the "special topics" idea because this lets you see whether they can do it for themselves or whether they are only able to follow pre-set curricula.
Ask how they'll ensure that the top students are being adequately challenged while the weaker students aren't being left behind.
Ask how they handle unruly students. Even though this is fairly rare at the university level, they should have a ready answer.
Have them explain some concepts to you and make sure for yourself that you are comfortable with how they explain them. (Similar to model lesson, but for specific topics.)


You may also want to mention things like office hours requirements, whether they'll get a TA, and related administrative stuff.