Not a reviewer, but a somewhat recent applicant. My largest project I was working on was not published around the time of application but I think was the most relevant thing in my application and was discussed in detail at every interview. It was a relatively ambitious collaboration (for a resident) that included using banked tumor specimens for bulk RNA seq, a novel computational method developed in collaboration with the computer science department to analyze the data and correlating this with patient response.
I used this as a clear example of the kind of research I hoped to do as a fellow and junior faculty. This generated a lot of positive feedback and I think proved that I had spent time developing a project and working through the mechanics of getting it off the ground.
I agree with
@gutonc that the first author papers in major journals are really the only thing that "count"; however, I will say that getting one of those as a resident who hasn't done a PhD or taken a year out for research often requires being in the right place at the right time in addition to being a research superstar. So don't sell yourself short if you are research motivated but haven't hit paydirt by the time you are applying and interviewing.