Hi OP, I had a whole big post I keep almost posting on this topic, having - somewhat unintentionally - tried a whole bunch of them.

Anyway, Hot Lola's or WooBois are the answers I'd give depending on if Sichuan pepper flavor is acceptable (Hot Lola's) or not (WooBois) for you, even though I eat at Roaming Rooster more than anywhere since they're easiest for me to get in that specific style. (Lucky Buns is also great, but I think they're just a bit too far off the "standard" chicken sandwich to really fit in.)