Leroy Sane bagged a brace and Robert Lewandowski was also on target as Bayern ran out 4-0 winners in Benfica.
The result was harsh on the Portuguese giants who were firmly in the game, and forced Manuel Neuer into two fantastic saves, before Sane curled a stunning free kick home 20 minutes from time.
Bayern also had two goals narrowly ruled out by VAR before they took the lead, close-range finishes from Lewandowski and Thomas Muller, the first the result of the ball striking the Polish striker's arm and the other through offside in the build up.
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Muller and Benjamin Pavard also saw efforts come back off the post, the latter after a fine stop from Odisseas Vlachodimos.
Ten minutes from time, substitute Everton headed into his own goal to double the lead after substitute Serge Gnabry pulled the ball back from the by-line. The former Arsenal winger was involved again in the third as he found Sane in the box, who unselfishly squared for Lewandowski to tap home.
Sane got his second in the closing stages when another substitute, Josip Stanisic, pulled back for the Germany international to slam home.
Bayern now have scored 12 goals in three Champions League games in Group E. Benfica are in second spot, a point ahead of Barcelona who beat Dynamo Kiev 1-0 at the Nou Camp.
TALKING POINT - WHO CAN STOP BAYERN?
The absence of Lewandowski was a big reason for Bayern failing to reach the semi-finals last season, as they fell to PSG on away goals. They look so good this term that it will likely take such an occurrence to keep them from winning the trophy again this time round. With key men like Leon Goretzka and Alphonso Davies out there was the possibility they might struggle at one of Europe's most intimidating venues against a buoyant outfit.
Though the game was far from one-way traffic, with Neuer making sublime stops from Darwin Nunez and Diogo Goncalves, Bayern also could have added to the scoreline on numerous other occasions.
The brilliant return to fitness of Coman gives them the most exciting of dimensions on the left and Gnabry showed with his second-half cameo, he was involved in three goals, that he will not quietly accept a part-time role. Muller shows no signs of sliding and Dayot Upamecano looks as solid as any centre back around. They have no weakness.
MAN OF THE MATCH - KINGSLEY COMAN (BAYERN MUNICH)
Coman has been a very good player for Bayern for five years, amassing over 200 appearances and winning all honours at club level, but performances like this make you realise he can lift his career up a notch in his first start after minor heart surgery.
Put simply, he was unplayable, showcasing dazzling orthodox wingplay that is seldom seen in the game at the top level.
He was a key figure for France as a youngster in Euro 2016 but was not selected for the World Cup two years later and a periphery figure in the Euros this summer. Next year in Qatar could be his time.
Benfica: Vlachodimos 7; Almeida 6, Verissimo 6, Otamendi 6, Vertonghen 6, Grimaldo 6, Weigl 7, Joao Mario 6, Rafa 7, Nunez 7, Yaremchuk 6.
Subs: Goncalves 6, Everton 5, Taraabt 5, Ramos 5, Pizzi 5.
Bayern: Neuer 8; Pavard 6, Sule 6, Upamecano 7, Lucas Hernandez 6; Kimmich 7, Sabitzer 7; Coman 9*, Muller 8, Sane 8; Lewandowski 7
Subs: Gnabry 8, Stanisic 7. Musiala 6, Tolisso 6, Richards 6.
33' Great save from Neuer. Nunez couldn't bring the ball down when beyond the Bayern defence, but then turned inside Sule, who was getting dangerously handsy with the Uruguayan, and then unleashed a rocket which the German 'keeper dived to his left and parried over the bar.
43' GOAL FOR BAYERN - NO! Lewandowski turns in Coman's close-range cross from the by-line, it looks like turned it home with his chest.....no, it was off the arm, surely VAR disallow it.....yes, they do.
52' GOAL FOR BAYERN - NO! Muller turns home a scrappy goal from close range after Coman again caused havoc down the left, beating the right back then pulling back to Sane. His shot was saved but then Muller turned home. Coman was slightly offside when the ball was played over the top - just his trailing boot. Muller remains on 49 Champions League goals.
70' GOAL FOR BAYERN! Sane gets his free kick right on this occasion. Curling the ball over the wall and out of the reach of Vlachodimos. A great free kick.
80' GOAL FOR BAYERN! An own goal doubles the score. Gnabry got to the by-line and seemed to run out of ideas but hopefully guided the ball towards Muller. Everton cannot direct his header away from his own goal.
83' GOAL FOR BAYERN! This is so unfair. Gnabry found Sane in the box and he was a little fortunate to get the ball come back to him after an attempted flick and then side-footed square to Lewandowski to finish.
85' GOAL FOR BAYERN! Incredible. Again Gnabry is involved playing in Stanisic on the right wing and he pulled back for Sane to sidefoot home.
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