Kim K -- Calling the Shots for New 'Pussycat Dolls' Show

Kim Kardashian is all set to return to the "Pussycat Dolls" ... only this time, she'll be running things BEHIND THE SCENES -- as the executive producer of a new PCD reality show ... TMZ has learned.

Kim signed a TV deal with "American Idol" honcho Nigel Lythgoe -- to be the E.P. for an upcoming reality show about the "Pussycat Dolls empire" ... that will feature the launch of a "new" PCD group.

One source tells us the newbies are "10 times better than the original group."

We're told Kim has a good relationship with PCD founder Robin Antin -- plus Kim really enjoyed performing with the group in Vegas a few years back.

Kim is telling friends she's "super excited" to work with Nigel because "he's the best in the business."