The Tanzania-born 20-year-old showed footwork the "King of Pop" would have been proud of as he dribbled past defender Jurien Gaari and nutmegged goalkeeper Eloy Room for his first goal in the 80th minute at Melbourne Rectangular Stadium.
After sticking the landing on a gymnastic back-flip, he put on a sequined glove thrown to him by an on-field photographer and danced a jig with Jackson's trademark crotch-grab.
Irankunda said the photographer was a friend who had given him the celebration idea in a chat on Instagram.
"He knows I'm a huge fan of Michael Jackson and his music, and it was just great to bring it out and show people," Irankunda told reporters, naming "Smooth Criminal" as his favourite Jackson song.
Irankunda followed up his first goal by sliding in his second less than four minutes later to cap the team's farewell to the home fans with a fifth goal before they head overseas to continue their World Cup build-up.
Irankunda's promise has excited Australia since he became the country's second-youngest player to score an international goal in a World Cup qualifier against Palestine two years ago.
A high-profile signing with Bundesliga giants Bayern Munich went nowhere, though, and he ended up loaned out to Swiss side Grasshopper before joining English Championship (second-tier) club Watford last year.
Tony Popovic overlooked him for selection in his first three international windows as Socceroos coach but Irankunda has made his mark since coming back into the fold and may be Australia's most dangerous forward at the World Cup.
Popovic said he was delighted to see Irankunda storming into the box to score his goals, having shown his marksmanship from long range previously.
"We want that to continue," Popovic told reporters.
"He's a young man that's growing in maturity, not just on the field but I think off the field."
Popovic deployed Irankunda as a substitute in both the Socceroos' friendlies against Cameroon and Curacao to try out different forward combinations.
They struggled for cohesion in both matches but improved when Irankunda came off the bench in the second half.
He will hope for a starting role at the World Cup for a team with much higher ambitions than their world ranking of 27.
"We want to be that group that goes all the way and potentially wins the World Cup," Irankunda said.
"No-one has the belief in us so we have the belief in ourselves."
Australia play their opening World Cup match on June 13 against Kosovo or Turkey, who meet in a playoff later on Tuesday, and will also face Paraguay and co-hosts U.S.
