The 28-year-old's combined time over two legs was 20 hundredths quicker than Swiss racer Loic Meillard - who had been fastest in the first leg - with his fellow Norwegian Lucas Braathen third, 49 hundredths adrift.
Kristoffersen's victory came on a course in a bad state due to the recent warm temperatures and it became a veritable battle against the elements when heavy snow fell on the second leg.
"I think that I skied intelligently on the snow, because that was a heck of a battle," said Kristoffersen.
Braathen was more direct saying: "My God that was quite a war!"
Admirably consistent it was Kristoffersen's seventh top-three finish of the campaign - his previous win came at Garmisch a fortnight ago.
The overall World Cup standings were unaffected as neither the leader Switzerland's Marco Odermatt nor second-placed Aleksander Aamodt Kilde - who trails by 340 points - competed in the slalom.
