P.B&J is the ultimate rock ’n’ roll sandwich. Take two pieces of heavy metal. Spread some sloppy grunge on one piece and psychedelic blues on the other. Put it all together and it sounds so tasty. Peter Anderson is the singer, songwriter, guitarist and mastermind behind “the hottest band on YouTube,” with 315 videos posted in five years. Jake Ericson is the faithful bassist. Like Spinal Tap, the trio has gone through multiple drummers — Antonio Davis is the latest. The 13-track concept album Progressive Concept, released in 2023, features songs written in each of the major keys.