That's when Jimmy realized he was a great lawyer. Also notice that his desert experience caused him to lose his fear of the courtroom. After facing the trauma of possibly being skinned alive, performing in court is a piece of (Cinnabon) cake.
The downside is that his desert experience affected him to the point where he suffers PTSD when he sees someone breaking a breadstick.
I think the black and white opening scene was Saul’s present day after going into hiding. I’m pretty sure the guy in the restaurant that made Saul nervous was from Breaking bad.
I noticed Saul seemed to be living pretty good for a fast food worker.