Rachel Leviss made a killing on the last season of "Vanderpump Rules," TMZ has learned ... which makes Bethenny Frankel's claim Rachel made less than her interns a bunch of BS.

Sources familiar with the situation tell TMZ Rachel made more than $350k for season 10 of the show -- nearly $20k an episode for a total of 19 episodes -- so certainly not chump change.

ICYMI, Bethenny told Rachel on her "Just B" podcast Wednesday that her own interns make more dough than Rachel did on 'VPR,' which came as a shock to Rachel.

Fans online slammed Bethenny's interview as embarrassing, and reminiscent of Howie Mandel's unhinged interview with Tom Sandoval back in April -- focusing more on his mustache than the cheating scandal.

Folks also pointed out the fact Bethenny didn't seem prepped for the interview, and she even admitted on the podcast that she had never watched the Bravo show and had only seen clips online after taking interest in Rachel and Scandoval.

So Bethenny either had no clue what Rachel really made, or she's completely overpaying her interns ... 'cause $350k ain't bad.

You'll recall, Bethenny and her attorneys have been hearing from dozens of NBC reality stars after firing off a legal threat earlier this month, claiming production employees have been tormenting the shows' castmembers. She's even been fighting for reality stars to unionize.

We covered the story on the latest episode of The TMZ Podcast, available on all podcast platforms.