The TV host joined us on "TMZ Live" and talked about the journey to the show's triumphant return.

The series made a comeback earlier this year for a limited run, and Mike says over the last year he got hundreds of letters from loyal fans imploring him to reboot the series.

So why now? Mike's simple answer -- COVID. During the lockdown, essential workers became headline news ... the relaunch seemed like a good idea to remind people of the kinds of essential jobs that make life work, especially during the pandemic.

Now get this ... Mike also rightfully gloated about his side hustle -- singing! His song,  "Santa's Gotta Dirty Job" with Country music singer John Rich was released in early December ... and boy, it was a hit!

No, really ... the song hit #1 for a week on Country Music charts, #1 on iTunes for 4 days -- and even took the top spot on the Billboard digital song sales chart.

As for profits, John and Mike are splitting it even steven and giving all of the proceeds to non-profit orgs.