Henson was making his first appearance for the club since joining from Saracens at the start of February.
The Wales centre crossed for Toulon's bonus point-securing fourth try in a bad-tempered match that saw three players sent to the sin bin.
In contrast Stade could only manage the one try, courtesy of centre Guillaume Bousses, and five points from the boot of Julien Dupuy.
Bayonne 26-16 Racing Metro
Racing Metro's title aspirations were dealt a blow as they went down 16-26 away to Bayonne.
But Bayonne out-scored their visitors by two tries to one while Benjamin Boyet kicked 16 points for the hosts.
Yoann Huget and Sam Gerber were the men to touch down for Bayonne while Mikaele Tuugahala scored a consolation try for Racing on the stroke of full time. Jonathan Wisniewski kicked the rest of Racing's points.
Last year's champions Clermont Auvergne made short work of Biarritz, running in six tries in a 41-13 demolition.
Added to two conversions from France scrum-half Morgan Parra and a penalty, that gave the home side a 23-0 lead which Biarritz never looked like relinquishing.
There were two consolation efforts from the visitors in the second half, but the lead increased as Clermont added three more tries of their own.
Montpellier edged closer to a position in the top two as they heaped further misery on basement club Borgoin, cruising past them at Stade Pierre-Rajon.
Montpellier touched down five times; Martin Bustos Moyano crossing over twice before Adrien Tomas, Francois Trinh-Duc and Santiago Fernandez all got in on the act. Bustos Moyano also kicked 17 points for the hosts.
La Rochelle squandered the opportunity to haul themselves out of the relegation zone as they lost away to Brive.
La Rochelle could only manage two penalties from the boot of Benjamin Dambielle and a drop goal from Remi Tales.
Castres slipped to defeat away at a determined Agen.
The visitors looked to have taken a big advantage early in the second half when Romain Teulet scored the opening try of the match with the sides locked at 6-6.
But two tries in a three-minute blitz from Maxime Machenaud and Saimoni Vaka turned the game on its head, and though a Teulet penalty kept Castres to within two points of Agen, Conrad Barnard's drop goal late on settled Agen's nerves.