The British diver moved himself out of fourth into the bronze medal position with his penultimate dive but clinched the gold with the most difficult dive in his repertoire in the sixth and final round. He had previously been crowned world champion back in 2015 but a diving error in 2017 attempting the same final dive cost him a medal of any colour.
And a second world title in Gwangju looked potentially out of his reach when lying 30 points behind event leader Steven LoBue with just two rounds remaining. An inward triple somersault with a half-twist nearly halved that deficit and a triple quad sealed the gold with a winning score of 442.20 points.
That final dive sealed perfect 10s across the board, matching the first ever perfect 10 which he had clinched during the Red Bull Cliff Diving World Series event in Lebanon.
The 2017 world champion LoBue had to make do with the silver with Jonathan Paredes completing the podium with the bronze.
Hunt, 35, has been in a class of his own this season, winning the Red Bull Cliff Diving events in El Nido, Polignano a Mare, São Miguel and Beirut, and is en-route to clinching his eighth overall title in the series.
Following his golden finale, Hunt said: "It's hard to explain your feelings after such a final. I'm still shocked. I learnt a big lesson in Budapest – I messed up with this dive because I couldn't handle the pressure. The execution of the dive was also not so secure then – I've improved a lot since 2017."
Iffland remains unbeaten in 2019 after pulling an amazing 20m high dive out of the bag in the final round to beat Red Bull Cliff Diving rivals Adriana Jimenez and Jessica Macaulay to retain her FINA World Championships title.
Mexican Jimenez led comfortably after three of her four dives with Briton Macaulay in second and Iffland out of the medals in fourth, but the 27-year-old Aussie had something extra in her locker though, executing a brilliant inward three somersaults with a half twist in the tuck position dive. With that she snatched gold by just 0.15 of a point, the smallest margin in the event's history, with Jimenez taking silver and Macaulay earning a bronze.
The Newcastle native now has two world golds after her 2017 Budapest triumph with Jimenez repeating her silver and Macaulay earning her first world medal.
"It's difficult to handle all those emotions at the top of that platform," said Iffland, "but I flipped them around and brought positive energy. That's why I love this sport."
With two rounds remaining, she is on track to win her fourth Red Bull Cliff Diving World Series title in a row after winning all 2019 stops so far.