The game came at the end of a tricky week for the Gunners in which they had lost 2-0 to Bayern Munich and played for over half the match with 10 men.
But they were at their brilliant best in the first half against Sunderland, Olivier Giroud bagging a brace to put them 2-0 up before Tomas Rosicky scored after a delightful passing move.
Asked where the Rosicky goal rated among those Arsenal have scored during his tenure, Wenger said: "It's one of the best and even one of the two Giroud goals was a great goal, with a great ball in behind from Jack (Wilshere).
"It's the way we know we can play, it's the way we want to play. When it's successful, of course you are extremely happy, because it reinforces your belief in the way you want to play.
"It was an important game for us firstly. We had given a lot physically, against Liverpool (in the FA Cup last weekend), against Bayern, with 10 men.
"To win today was of course vital. We did the job in the first half very well and, after that, it was a convincing win."
Wenger had particular praise for Giroud, who sat out the Bayern loss but made a big impact on his return to the side.
"You can take the videos out and see how he has improved compared to when he arrived," said the manager.
"His link play is much better, his movement as well, and it's good that he came back and scored two goals."
Wilshere seemed to pick up a knock towards the end of the match but Wenger said: "Jack has a hamstring problem but it just tightened up, I don't think it's a pulled one."
Arsenal's title rivals Chelsea and Manchester City were also victorious on the day and Wenger added: "That's interesting!
"It's exciting but we have to focus on our performances, and keep that spirit in the side - then we have a chance."
Arsenal's club record signing Mesut Ozil missed the game with a thigh injury but Wenger said: "It was a kick, he should be available next week."