The Kiwis outclassed Argentina to take Sunday's final 38-14 in Cape Town, celebrating their first tournament victory since March 2016 with a traditional Haka war dance.
The result means coach Clark Laidlaw's men rise to the top of the World Series standings following their second-place finish in Dubai last week.
"I'm so proud of how the boys played this weekend and last weekend," said captain Scott Curry, after tries from Vilimoni Koroi, Tim Mikkelson, Regan Ware, Sione Molia and the irrepressible Joe Ravouvou helped steer his side to victory.
"We started fresh and really worked for each other and that's what won it for us."
It could have all been so different. New Zealand were soundly beaten by the US on day one of the action at the Cape Town Stadium, going down 22-0 in the preliminary match, during which American speedster Carlin Isles hit speeds
of 37kph (23mph).
But they put the disappointment of that shock defeat behind them, overcoming Australia, Spain, England, South Africa and finally Argentina to take the full points on offer.
Two tries from Ravouvou, the game's standout performer, helped the All Blacks run out comfortable winners against Argentina, who were playing in their first final since the Cape Town edition in 2015.
New Zealand's last championship victory came in the 2013-14 series -- completing a run of four-straight wins -- but they have failed to finish higher than third in the past three seasons.
"It could have gone either way after we lost our first pool match against USA yesterday but day two is another day," reflected Curry.
"We'll look forward to our home tournament in Hamilton coming up soon -- it's a new city and they really love their rugby there."
Hosts South Africa, who won the series opener in Dubai
last week, beat Canada 19-17 in the Bronze Final to ensure they keep pace with New Zealand in the overall standings.
Last year's champions trail the All Blacks by just two points heading into the third event of the season in Hamilton, New Zealand, which is a new addition to the World Series after Wellington was dropped from last year's schedule.