'Vanderpump Rules' Star Scheana Shay Works a Shift at Chili's in Uniform

Scheana Shay was slinging drinks somewhere other than SUR this week -- working a shift at a Chili's Grill & Bar instead ... going back to her server roots, pre-fame!

In videos obtained by TMZ, the "Vanderpump Rules" star was seen rocking a Chili's uniform Wednesday night while running food to tables and whipping up drinks behind the bar in L.A.'s San Fernando Valley.

It was pretty surreal to see, especially considering Scheana used to work at a Chili's back in the day -- before she skyrocketed in Hollywood by landing on the hit Bravo show.

Take a look ... Scheana was back in the groove, looking focused and attentive to customers -- several of whom recognized her right away from 'Vanderpump.' She even took selfies with some guests ... indeed, it was a true starstruck Hollywood moment for the folks of Encino.

Now, don't expect Scheana to be clocking into Chili's full-time ... as her appearance here was part of her new collab with the bar and grill ... so, yeah, it was a temporary promotional thing.

Scheana and her 'VPR' castmate, Katie Maloney, recently introduced Chili's new Espresso Martini -- which swaps out classic vodka with Reposado tequila. BTW, cameras weren't rolling for this ... so this was just a one-off thing Scheana did to plug her partnership with Chili's.