Coach Julian Nagelsmann made seven changes to the team that drew against Borussia Moenchengladbach at the weekend with an eye on their Champions League game at Inter Milan next week.
His team needed time to settle in and new signing Ryan Gravenberch slotted in for a deserved lead in the 35th minute despite a gutsy performance by the hosts.
French teenager Mathys Tel, who also arrived this season, confirmed his status as one of the most exciting prospects in European football when he rifled in a fine solo effort on the stroke of half time.
Sadio Mane, another new signing, made it 3-0 in the 53rd following a quick break to put the game to bed.
Tel should have scored again when he was sent through with only the Viktoria keeper to beat but Ben Voll stood his ground to deny the 17-year-old.
Substitute Jamal Musiala did better four minutes later, slotting in from close range before fellow substitute Leon Goretzka, on his comeback from injury, completed the rout.
Check out the match summary of Bayern's win with Flashscore.
