Some might think that variety shows in the 70's were a dime a dozen. Seems network executives felt any performer worth their salt would front a hour long comedy-variety show. Some worked (i.e. Flip Wilson, Donny & Marie). Some didn't, mostly because those same network executives thought a flavor of the month (i.e. Starland Vocal Band) could extend their 15 minutes with a weekly show.
Sonny & Cher fall into the former category.
What you might not know is that the then-husband-&-wife team of Sonny Bono & Cher were working the nightclub circuit when then-CBS executive Fred Silverman contacted them about doing a weekly TV show after catching their act one night. The hits had stopped for a while, although Cher scored a solo hit with "Gypsies, Tramps, & Thieves" the year she & Sonny launched their show, in 1971.
The Sonny & Cher Comedy Hour lasted three seasons, ending by mutual agreement in 1974 when the couple separated, then divorced. Subsequent solo series didn't work so well, including Sonny moving to ABC to front a Sunday night show in the same time slot that would later claim variety shows fronted by Bill Cosby and The Brady Bunch among their victims. The two would reunite to revive the series after Cher married Gregg Allman, but the magic just wasn't there anymore.
On the surface, Sonny & Cher's show was modeled after Carol Burnett's hit series, with musical numbers mixed with outrageous comedy skits. Check out this "Vamps" skit with guest stars Larry Storch (ex-F-Troop) and Wilfrid Hyde-White (later of The Associates and Buck Rogers in the 25th Century) from season 2 in 1972.
As a by-product of their show airing on CBS, Sonny & Cher would subsequently team with Scooby-Doo on the canine sleuth's Saturday morning show, but there were no musical numbers.
I will take this time to mention that as of today, GetTV, still another digital network that mixes movies with old, long unaired shows, has been added to Time Warner Cable's lineup. Sonny & Cher airs on Monday nights and Sundays (check listings).