Gabriel Jesus scored four as the holders showed no mercy on their League One opponents on Wednesday, taking their goal tally to 16 in the space of four days following Sunday's 7-0 hammering of Rotherham.
Kevin De Bruyne - who set the tone after just five minutes at the Etihad Stadium - Oleksandr Zinchenko, Phil Foden, Kyle Walker and Riyad Mahrez were the other scorers in a one-sided semi-final first leg.
City spurned a host of other chances and also had a good penalty claim dismissed following a VAR review in what was a record victory in an English domestic cup semi-final.
"We spoke about travelling to Burton with as big an advantage as possible but we didn't expect to score so many goals," said Guardiola.
"It's the best way to respect the competition and respect the opponents. If you are 4-0 up and forget to continue, you don't have respect for the competition or your opponent. The best way is do what we have to do."
It was a tortuous night for Burton and their fans, many of whom had also endured an arduous journey after being caught up in severe traffic problems due to a police incident on the M6 in Staffordshire.
"They're professional, they keep going and don't ever ease off at any point," said Burton manager Nigel Clough, a former City player. "They don't just beat you, they annihilate you.
"It's not very pleasant when you're on the other end of it but that's what they're capable of.
"If that front five players are playing in the semi-final of the Champions League they'll give Real Madrid problems, or whoever they're playing. So, they're going to give us problems."