How do you interview someone with more experience than you?
Next week i'll be interviewing some contractors for a 6-month senior Dev position on a project. I'm an OK programmer myself, but nothing special, and at the moment i'm struggling to think of what questions to ask them, or what coding challenges i'd set, since the answers would likely go over my head anyway.
The project is an ASP.NET MVC application for an intranet.
My personal thought was to have them write a trivial MVC app that pulls some data from a DB during the interview, showing that they can implement a testable, loosely coupled application, but i don't know if this is too trivial. From it i would expect them to have implemented a couple of tests, set up dependency injection, and probably use a repository instead of fat controllers.
Any ideas, or is what i'm suggesting a bad idea? The coding part of the interview would likely last about 40 minutes. I timed myself doing what i'd planned and it took me just over half an hour. The candidates would have seen the requirements for the application a couple of days prior to the interview.
From thinking about it a bit more, perhaps i should start off with a tightly coupled app, and ask the candidates to refactor it instead, and implement some tests?
Edit: With respect to Rob's comments below, i'd like the answers to more focus on what i'd got planned (But all answers gratefully received)