She charged over for a second in the 57th to take the game out of England's hands at 28-4 before she put the icing on the cake with a powerful run to grab her third in the 78th.
Amazingly, she could have had two more but twice elected to hand the ball off to a teammate with the tryline begging.
First, in the 67th, the Kiwi Ferns created space on the edge and Hireme looked certain to score however she passed it to Hilda Peters, despite having the line wide open in front of her.
Then with the final play of the game she busted through five tackles and was in the in-goal however unselfishly handed it off to skipper Laura Mariu.
After a mixed showing in their 36-8 win over Papua New Guinea last week, coach Tony Benson would have been happy with his side's complete performance heading into Saturday's final.
The three-time champions are seeking to regain the World Cup after losing to Australia in the 2013 final.