The Gunners eventually broke the deadlock in the 32nd minute as the hosts broke on the counter led by Alex Iwobi, who slid the ball to Aubameyang for the close range finish.
Substitute Mesut Ozil got in on the act in the 74th minute as the German slotted home from close range after getting on the end of Lichtsteiner's cross.
And speaking after the game, manager Unai Emery was unhappy his side couldn't keep their clean sheet.
It can be argued that the goalkeeper was not at fault for either of the two goals conceded, but he had a relatively quiet evening aside from that.
"I think we played well in the first half and at the beginning of the second as well and we scored four goals", he told reporters, with Everton up next in the English top flight on Sunday.
If Gabbiadini fails a late fitness test, Hughes is likely to name Charlie Austin and Shane Long - who have failed to score any league goals this season - as his strikers against the team that has conceded the fewest goals this season. We are giving chances to many players to find the pieces and for the confidence. We push each other and I think the competition with us is very good. So, when they started to attack more, there were situations where we can create chances by playing from the back.
"It is good for many players".
"Our challenge is to be competitive for 90 minutes of each match and this is one thing to improve".
"I think (Liverpool) are at a point in their development now where they clearly need to go for the Premier League title now", he added. We both can improve and it's still going.
"I think the first 60 minutes were good with imposing our ideas against them and also, little by little in the match, winning battles on the pitch to be near to scoring", he said.