Applied in person. Three part interview, one when I turned in my application and two scheduled interviews and each with several different members of the staff. Very fun and laid back interview. Basic interview questions and the most unexpected question was what would I cook for dinner to impress them. Also, know their products well.
Applied online and had one in person interview with the captain. It lasted maybe 10 minutes. Got a call a week or so later that I got the job. Very fast process.
It's two to three interviews, the final with the Captain (or highest manager) of the store. The interviews are largely to get to know your personality and how well you would do at customer service.
The interview process was absolutely wonderful! I didn't feel stressed or nervous and it felt like I was just chatting with a friend! Trader Joes is a great company and the interview was great.