Sara Bareilles is going to write New York City a love song – figuratively speaking, at least. “When people say, ‘You seem so East Coast,’ I was always like” – she lowers her voice to a whisper – “‘Thank you.’” It appears that while you can take the girl out of California, you can also take the California out of the girl. Bareilles seemed like a West Villager trapped in a Eureka-to-Los Angeles gal’s body well before she made the move East six years ago. “I’m not dissing California at all. I loved growing up in a rural area with acres of redwood forest and lots of animals and going to school in L.A. But I have really responded to the temperament of New Yorkers. I like the directness. I like the no-bullshit. I like the rough-around-the-edges. I’m into it.”

The irony is that we are having this NYC-glorifying conversation in Los Angeles, barely a mile from her old stomping grounds of UCLA, and not much farther from the Westside haunts where she wrote and recorded “Love Song,” the breakout hit that earned Bareilles, now 38, her first two Grammy nominations, in 2009. She hung around town the day after this year’s Emmys, where she cheerfully fell short of a supporting actress award for her role as Mary Magdalene in NBC’s “Jesus Christ Superstar Live in Concert.” As she half kids, she’s well on her way to losing out on the full EGOT, needing only a thwarted Oscar nomination to complete her catalog of near misses.

But when we think of Bareilles and awards shows now, we conjure one that transpires at Radio City Music Hall. A few years ago, she did the second-most-ultimate New York thing anyone can do, which is write the score for a Broadway musical, Waitress, now two and a half years into its run and touring nationally to boot, drawing a happy mixture of tourists who’ve never heard of her and fans brought in by ads blasting the not actually in the show “Love Song” and “Brave.” (“When you listen to the score, though, I don’t think it’s a far stretch to my records – I only have about five tricks up my sleeve.”) To top that, this year she made the most quintessential New Yorker move possible: co-hosting the Tonys (with fellow LA-to-Great White Way émigré Josh Groban).

Her Manhattan idyll, which was originally going to be a brief walkabout, is going on six years now. “Where I was in my life here in LA was very comfortable – not unhappy, not unsatisfied, just comfortable, and slightly uninspired. I was going to the same places every day and seeing the same people. The grooves were worn really deep for me, and I was not encountering new information. So I thought, OK, I’ll go on this little adventure, and I stayed in random people’s apartments and walked across the city at all hours of the night and dressed up, and I was encountering myself in a new way. When I got to the end of that first month, I really liked the person I met within myself.”

The writer in her pauses. “That sounds really cheesy, but it coincided with some meetings that had to do with Waitress and with my book coming to fruition. It was like a neon sign. It was so inviting to go toward it.” A month turned into a year, which turned into “realising I didn’t have a desire to return to LA. I didn’t feel like my story in New York was done. I stuck.”

She quickly felt more accepted by the theatre community than she had even by the music community, as “a newcomer coming into this beautiful legacy, where there was a lot of room for people to be brats about it.” Still, she says, agreeing to score Waitress was sheer naiveté on her part. “I had no idea what I was signing up for – just not even a clue. And I love musical theatre and don’t think of myself as being someone who’s unfamiliar with the theatre, but when it came to how involved and how painstaking and how long that process would be… It was the greatest. It’s changed my life 180 degrees.”

Waitress is touring around the country in places like LA’s Pantages Theatre and opening in London in January; against all investor odds, it’s stayed put at the Brooks Atkinson. The show is at that wonderful place deep into a run where the stunt casting is starting: Welcome, Al Roker! (For the month of October, he’s diner owner Joe.) The first of her own two runs in the lead role (the second of which was early this year) won her the 2017 Audience Choice Award for favourite replacement, which she keeps next to her piano. But her current replacement as replacement is no stunt: “I remember saying to people that my wish for the show is that we get a beautiful fatted calf of a first year, and that we don’t limp across the finish line. And then we got to year two. Now we have our first person of colour in the role of Jenna, and that’s a really proud moment for me. I’m just such a fan of Nicolette Robinson.”

She’s also taken to acting in musicals Off-Broadway – to the extent that the Hollywood Bowl and 9.4 million NBC viewers count as “Off-Broadway.” Preceding her pair of Waitress runs, in 2016 she did a two-night stand at the Bowl assuming the title role in a live-to-film staging of The Little Mermaid. Then, this April, there was Jesus Christ Superstar, fulfilling some unlikely life goals set when she was a childhood Alan Menken and Lloyd Webber-Rice freak serenading the redwoods. The biblical maxim about perfect love casting out all fear went only so far when she was doing the show live, sans net. “I was shaking in my sandals. But as a cast, we were so protected and so encouraged to just play and connect with each other, and they were so smart to create the format where we had a live audience with us in the armoury. We felt so safe. But I was nervous. John Legend, oddly, was just cool as a fucking cucumber. So I’m thinking to myself, if Jesus isn’t stressing, I should just relax.”

She’s gone from Jesus to a contemporary guru: producer T Bone Burnett, with whom she just wrapped up her first album of non-Waitress material in five years; it’s in the mixing phase and set for release early next year, possibly to be preceded by a single this fall. “That’s been kind of a bucket-list moment for me. I’ve been a fan of his my entire life. We did a lot of live recordings with the studio band playing and singing at the same time, which is new for me. The recordings aren’t perfect, but they have soul, and that’s what I was really craving, is to make something that was just honest and imperfect and a truthful representation of where I feel like I am. And T Bone, he’s the dude for that.”

“I think there’s a lot to say right now about the world, so I didn’t shy away from that. One of the things I’ve been struggling with is realising that the world is chaotic, and we have to just exist in spite of it, because it feels especially chaotic in the last, ohhh, couple years. So I wanted to address political themes. But the thing that moves me the most is to talk about emotional architecture and what it feels like to be alive amid all this.”

They recorded in LA, but New York is likely to infuse the record. “The thing I always love about New York is the humanity of the city. It’s not polite in any way. This is a city that’s growling and dirty and congested, and that’s the harsh part, but I think it breeds compassion. I’ve never been in a place where people were more willing to help each other. It’s a terrifying world sometimes, but we’re all in it together, down to the trains and the sidewalks. And if I make a snap judgment about someone walking down the street, I’m 100% of the time totally surprised. I get my ass handed to me on a daily basis in New York, and that’s good for me.”