The interview process was very simple. The professors were not even planning to add any more TA positions when I was applying. But, they ended up needing a few extra people. I reached out to the professor to talk about my interest in the position. Then I had an interview with multiple professors and a current TA. I heard back within a couple days.

This is super easy and there is no interview at all. You just have to submit your resume and they will most likely hire you. This is a very nice job to have on your resume.