The Carabao Cup holders romped to victory after going behind.
Six academy players made their debuts on the night, while another teenager – Cole Palmer – added the final flourish with a superb first senior goal for the club in the final moments of the third round tie.
Phil Foden scored one and had two assists to take man of the match honours, but the night will be remembered for the youngsters who made their mark.
Conrad Egan-Riley, Finley Burns, Luke Mbete, Josh Wilson-Ebrand and Romeo Lavia started as Guardiola named a lop-sided team – a powerhouse attack featuring Foden, Kevin De Bruyne, Raheem Sterling and Riyad Mahrez playing in front of a defensive unit untested in senior football.
They got their first examination when Brandon Hanlan put Wycombe in front with his first goal for the club 22 minutes in, but responded superbly as goals from De Bruyne, Mahrez and Foden put the result beyond doubt before half-time.
Ferran Torres added a fourth, Mahrez got his second late on and then Palmer rounded things off in style, running from his own half before bending the ball into the net.
“I just have to say thank you to the academy,” Guardiola said. “They all do an incredible job.
“You have the feeling that we have not just one or two potential players but many of them. The academy gives them the right values to become good professional players and they have the talent.
“We have the feeling that we can count on them…We saw it today a little bit and we know how good they are. As manager of the first team I can enjoy it, I can use them.”
Mbete and Burns were handed the unenviable task of marking Wycombe’s veteran forward Adebayo Akinfenwa whose Wikipedia page suggests he would be capable of bench pressing their combined weight.
Vulnerability from set-pieces was exposed when City failed to clear a corner to leave the opening for Hanlan, but on the whole they look calm and composed, and comfortable playing out in the manner Guardiola expects.
“They faced a legend of English football, it was an absolute pleasure to meet him,” Guardiola said of Akinfenwa.
“It’s not easy to do it but they did very well. We are going to review the game and show them how to solve the problems. But there was not one bad performance.”
It was pretty much the perfect night for Guardiola. While the youngsters impressed, Foden shone on his first start of the season, and De Bruyne took another step as Saturday’s trip to Chelsea looms.
“Phil has been injured for two months but Phil doesn’t need many games to get his rhythm,” Guardiola said. “He lives 24 hours a day to play football and his physicality is sharp.
“Kevin, geen, he needs a proper pre-season, he has been injured since the Champions League final with what (Anthony) Rudiger did, then the European Championships and the national team.
“He needs rhythm, but that is why it is so good he got 90 minute, knowing it is still not perfect but step-by-step. Now is the moment to know Kevin is starting to be ready.”
Wycombe were in dreamland for all of seven minutes, but still enjoyed their night in Manchester.
“I didn’t get carried away enough to think there was a great shock on the cards,” boss Gareth Ainsworth said.
“Their front five, wow, and I’m not disrespecting their back five, they were brilliant as well.
“They’ve got some players who are going to be superstars, but we learned a lot and we had that moment on 22 minutes when Hanlan got his first goal for the club in front of our fans at the Etihad – fairytale stuff.
“I hope at the end of the season we’re saying we lost to the winners.”