I like live coding challenges, something like a ~2 hour pair programming session, ideally modifying an existing project. I invest as much time as each candidate, while we are both exploring whether we want to work together.
One approach that I've encountered (with a YC company) is that the first interview was actually a code review. One of the founders asked me to review some SQL DDL, some backend API endpoints. The DDL was missing some indices that were needed for the queries. It was using an integer ID field. The API endpoints were missing input validation, error handling, etc.
I thought this was a GREAT way to start an interview that tested for depth of experience and platform/language knowledge.
This actually inspired me to build https://coderev.app because the tooling for this felt like it would be clumsy for both the interviewer and it was certainly for me as the interviewee.
But a lot of times, seeing a candidate's portfolio -- if they have one -- is probably even more insightful than any coding exercise. When I've been on the hiring side, one of my favorite things to do is to look through a candidate's GH and ask them questions about projects they've done, why they chose specific technologies, etc.