The show debuts in America on Friday (02Nov12) and Stewart is credited as an executive producer, but he also co-created the series, in which MCEntire plays a Nashville, Tennessee mum forced to move her three kids and her mother to the California coast after her rock star husband cheats on her and leaves her broke.
And Stewart accepts the fact that he's behind the show might surprise many.
He tells Wenn, "My mind moves in mysterious ways! I became fascinated with Nashville after my first real stay there a few years ago... (Then) I went with a few friends to Malibu... and for some reason insisted we all wear country outfits, cowboy hats, etc.
"I made a little film too and put some music to it and then I started to invent a world where the two places collide. I then got a guy who worked at my management company to come up with some logos and started to kick around the story in my head. I came up with the idea that a very messy and public divorce happens in Nashville between two country stars and the female moves as far away as she can to Malibu with her feisty mother, her kids, etc.
"I then proceeded to write the story and synopsis with my in-house writer Dave Harris. Once we had that finished, I took the whole concept in a special box with story treatment, character breakdown, music, even hat and T-shirt in a wooden box to the late, legendary producer Laura Ziskin and showed her. She immediately loved it and we became partners to pitch the project."
And a chance encounter on a plane the day after he and Ziskin chose MCEntire as their leading lady made Stewart realise he was destined to find success with the show: "Almost the next day I sat down on a plane next to Reba's stepson, music manager Brandon Blackstock, we got talking and he mentioned he worked with Reba and I said I had a concept for a sitcom called Malibu Country. I said, 'Can you get this to her?' and he said, 'Sure,' so I e-mailed him the whole presentation and then I sent the box full of stuff."
Stewart's music also features on the show - he has co-written a song with MCEntire, which will feature in the pilot episode.