The 35-year-old Spaniard made a winning return after a five-month break, recording a 7-6 (6) 6-3 win in Sunday's final.
Nadal entered the tournament as a way to warm up for the Australian Open, set to start on January 17.
His trip to Australia was initially in doubt due to an ongoing foot injury paired with his recovery from covid-19.
But neither looked to hinder him as he dispatched Lithuanian Ricardas Berankis and Finland's Emil Ruusuvuori this week en route to the 89th trophy of his career.
Maxime Cressy made Nadal work for his prize, saving five break points in a close-run first set and also being denied a set point in the tie break.
The second set wasn't much easier either, with Nadal being forced to fight back to 6-3 after being broken in the third game.
The Spaniard eventually sealed the win after an hour and 44 minutes of play, and with the first Grand Slam of 2022 now just eight days away, the 2009 Australian Open champion will be keen to rest up.
"It means a lot to be back and with a trophy in my hands," Nadal said.
"I feel privileged and a very lucky guy to be here again. I am coming back from some challenging moments in terms of injuries, so I can't be happier."