Takanashi, 16, was in third place at the end of the first round with a leap of 96m and a total of 132.9 with American Hendrickson leading the way after jumping 98.5m for 134.8 overall.
However it was not to be Hendrickson's day as Takanashi's second effort proved just too good for the World Cup champion, who collected nine wins on route to the first-ever title last season.
Takanashi leaped 98m for an overall total of 265.2 with Hendrickson only managing 95m in reply for 261.4 as the Japanese ski jumper recorded her second World Cup win in Lillehammer.
Home hope Anette Sagen, who was part of the Norway's victorious mixed team on Friday, was second after round one but, thanks to Takanashi, dropped to third with an overall score of 258.9.
- Sports & Recreation