This is more or less what happened when I was hired for my current (tech job): I was asked about a real life problem by the interviewer (my soon-to-be colleague/manager) and I explained how I would have dealt with it (my thought process etc..). I asked question when I didn't know something, and I also wrote an email few hours/one day later confirming my interest for the company and adding a couple of things that could have not been clear during the interview about my skills. And when I went there for the second interview, as I had studied a bit more on their real problem, I had the opportunity to add few more thoughts on it.