Fabien Galthie’s men dominated the opening 20 minutes and Ashton crossed the whitewash for his 22nd try of the domestic campaign, overtaking Napolioni Nalaga’s 2008/09 haul for Clermont Auvergne.
Although Toulon were not playing at their usual home, with the 2014 champions moving it to Marseille, it did not affect the play-off contenders.
They scored twice more through Semi Radradra and Mathieu Bastareaud before Anthony Belleau extended their buffer to 22-0 with a penalty.
Vincent Martin provided a response for the visitors but Facundo Isa barged over to give Galthie’s charges a comfortable buffer going into the interval.
Montpellier battled in the second period and put pressure on the opposition rearguard, but they initially struggled to get their reward.
Vern Cotter’s men did finally cross the whitewash via Gabriel Ngandebe, but it was Ashton’s – and Toulon’s – day as Belleau effectively completed the win from the tee, despite Kelian Galletier’s consolation score.
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