The reality star was front and center Wednesday night at his establishment in Hollywood, Schwartz & Sandy's, where he was playing bartender for a bunch of people who swung by after the premiere for Season 11 of 'VPR' ... where Tom was also in attendance.

Check out this video we got of him slinging drinks and feeling himself -- he's got that Tom Cruise 'Cocktail' vibe ... which echoes how he presented himself at the Hollywood Palladium.

Tom was flashing smiles and posing confidently -- and more importantly ... folks noticed he was rocking another lightning bolt necklace, which got him in hot water last year.

You'll recall ... this style of necklace was one half of another matching accessory that Rachel Leviss had been wearing before their affair was exposed ... so it serves as a bit of an in-your-face reminder that Tommy boy cheated on Ariana Madix -- a relic of Scandoval.

That's why it's fascinating to see him rock a similar one almost a whole year later so proudly. Even more eye-opening ... the fact that eyewitnesses tell us Tom was asked about the lightning bolt and the fact he was still wearing it ... all he said was "Yup!"

As for the premiere itself ... it was a buzzy event that featured the whole cast, who certainly seemed to be giddy to get together and show off what they'd been filming in recent months.

In fact, Scheana Shay busted a move to her song, "Good as Gold," and we got a clip too. And in terms of the actual episode -- which will air at a later date -- best believe Sandoval is still top of mind for everyone ... although, he himself doesn't show 'til the very end.