A fourth top-flight win in succession since the return of coach Jupp Heynckes opened up a six-point advantage over rivals Dortmund, who slipped to third after RB Leipzig - four back from Bayern - beat Hannover 2-1 earlier on Saturday.
Bayern's trajectory starkly contrasts with that of BVB, who have seen their five-point lead after seven matchdays vanish and their hopes of Champions League progression all but dashed amid a run of just one win in seven in all competitions.
Arjen Robben became Bayern's highest-scoring foreign player in the Bundesliga when his 93rd goal for the club finished off of a lovely move, with Robert Lewandowski returning to haunt his former club again by doubling their lead before the break.
Lewandowski was deemed not to have got a touch to a cross from David Alaba - who was forced off with a hamstring injury in the second half - that ended up in the back of the net as the Bavarians put the result beyond doubt in the 67th minute.
Pierre-Emerick Aubameyang failed to take his chances as his barren run stretched to five matches, but a consolation strike from Marc Barta may not be enough to stop Peter Bosz going back to the drawing board after a chastening defeat that underlined their change in fortunes.
After Aubameyang wasted his first chance of the match, Robben rounded off an exquisite Bayern move to give Bayern a 16th-minute lead.
James Rodriguez brought a sublime cross from Thiago Alcantara – in as one of four changes from the side that beat Celtic 2-1 in the Champions League in midweek – down on his chest at the back post before laying off for Robben to pick out the top-left corner with a sweet strike from just inside the box.
Dortmund proved a threat on the counter-attack despite being penned inside their own half for long periods, Sven Ulreich racing off his line to stop Andriy Yarmolenko steering home from Gonzalo Castro's pass as the match sprang to life.
Bayern immediately broke and Lewandowski saw his drilled shot tipped over by Roman Burki - making his 100th appearance for the club - before Shinji Kagawa pulled wide as BVB countered from the ensuing corner to cap an enthralling two minutes.
Dortmund were made to pay for their missed chances when Lewandowski flicked Joshua Kimmich's cross home, a deflection off Julian Weigl looping the ball over Burki.
A foot injury meant Sokratis had to be replaced by Jeremy Toljan before half-time and the hosts' new centre-back pairing left Lewandowski unmarked within three minutes of the restart, the leg of Burki stopping him heading in his second.
Dortmund passed up a glorious chance to halve the deficit when a lack of communication between Aubameyang and Yarmolenko saw them stop one another from converting Christian Pulisic's cutback.
That proved costly in the 67th minute when Alaba's cross was missed by Lewandowski and Burki was unable to stop it finding the net despite getting a hand to the ball.
Bosz's side pulled one back with two minutes remaining, Bartra curling a fine finish across Ulreich from the left side of the box after Pulisic did brilliantly to keep possession in the corner.
Castro missed another opportunity in stoppage time and the makeshift right-back's strike provided short-lived relief amid an increasingly dismal run for Dortmund.
