Postecoglou: Spurs just getting started after Son routs Burnley
Postecoglou's side bounced back after their disappointing midweek League Cup exit at Fulham to record a third successive Premier League victory.
Lyle Foster's fourth-minute opener for Burnley could have sparked another Tottenham flop, but the north Londoners hit back in style thanks to Son's lethal finishing.
The South Korea forward equalised in the 16th minute before Cristian Romero and James Maddison scored to put Tottenham in charge.
Son netted twice in four minutes just after the hour for his first hat-trick since September 17 last year.
Josh Brownhill's late goal was no consolation for out-classed Burnley as second placed Tottenham extended their unbeaten start to the league season to four games.
Asked if Son's performance showed how Spurs can cope without Harry Kane following the England captain's move to Bayern Munich, Postecoglou said: "It's not exactly why but it's one of the reasons.
"I've got a picture in my head about what I want the team to look like and I keep saying we're still at the beginning of it.
"We're still building and there's a lot to be done. It's about putting all the pieces together."
Losing Kane was a huge blow to Tottenham ahead of the new season, but Postecoglou said their record goal-scorer's departure could allow others to shine.
Son and Maddison will be key to Postecoglou's overhaul as the former Celtic boss tries to bring entertaining football to a fanbase staved of eye-catching performances during the dour reigns of Jose Mourinho, Nuno Espirito Santo and Antonio Conte.
"There are some really good footballers in this club and they have the ability to play in the way this team needs to set up," Postecoglou said.
"Sonny, whether he's playing central or right, he's got all the characteristics to play the way we want to play.
"I thought today was a real testament to Sonny, Madders and Romero, the way they embraced that responsibility not just with words but with actions and not just on game day but on a daily basis.
"That's as encouraging for me as anything because as good as they are individually, they have that team spirit and that's important for me."
