Tom Sandoval Talks 'Scandoval,' Lets Howie Mandel Shave His Mustache

Tom Sandoval is opening up about his affair with Raquel Leviss in a slightly unhinged interview with Howie Mandel -- one where he, apparently, decided on the fly to remove his signature mustache.

The "Vanderpump Rules" star talked about the 'Scandoval' on Tuesday's episode of the "Howie Mandel Does Stuff" podcast ... claiming he's been learning a lot from the experience of cheating on his longtime GF Ariana Madix.

He said there was "no thrill" in it for him, just an anxiety-filled ride. Tom also revealed the first time he kissed Raquel was before she kissed his business partner, Tom Schwartz ... and claims he called things off with Ariana on Valentine's Day.

Tom goes on to complain about being so recognizable, which is when Howie offers to get rid of the stache. We're not saying it was planned, but for some reason, Tom had all the tools with him to get it done.

This is where it gets a little odd -- Tom's moment of vulnerability turns into a DIY trim ... switching from razor to scissors, then to a different razor before his upper lip is bare.

There is one funny moment when Howie's trim job gets a little too, umm ... Adolf-ish for Tom's liking.

As we reported, Tom was rocking out Friday with his band The Most Extras -- it was the debut of his 'stache-less face.