Not a day goes by that Bernadette Peters doesn’t miss her old friend Stephen Sondheim.

During our lunch at Cafe Luxembourg, she confided in me, expressing how he continues to occupy her thoughts daily. Recalling her dreams about him and finding solace in singing his songs, she deeply feels his absence, longing for his presence.

Returning to Broadway after a hiatus of seven years, Peters is gracing the stage alongside Lea Salonga and a cast of 15 others in a captivating tribute to the renowned composer known as “Old Friends.”

Emotions run high at the Samuel J. Friedman Theatre as the audience is spellbound and moved to tears whenever the celebrated actress steps into the limelight, owing to her pivotal role in breathing life into these enduring melodies.

Peters, 77, originated some of the great Sondheim parts: the rapping Witch in 1986’s “Into the Woods” and model Dot in 1984’s “Sunday in the Park with George.”

Later, the New York native starred in revivals of his “A Little Night Music” and “Follies.” 

But the collaboration — some have called her his “muse” — all started with the out-there George Seurat musical “Sunday.” 

“When I first met him, he made me nervous,” Peters said of Sondheim, who’d already delivered notoriously tricky shows such as “Sweeney Todd” and “Company.”

“The first song I got was the first song, ‘Sunday in the Park with George,’ with all those words. And I was nervous like crazy.”

The jitters soon went away, though. “He was very kind to performers,” she said.

Peters’ favorite memories of Sondheim, who died in 2021, were when he’d come back to her dressing room and give notes. 

“I was lucky that the writer was there for me to talk to and ask questions. ‘What did you mean when you wrote that?’ It’s a great gift.”

And the experience, which got her and her friend and co-star Mandy Patinkin Tony nominations, proved life-changing.

“That show was so remarkable and it opened me up so much that I thought, well, I’ll just do any show that [Sondheim and James Lapine] write that comes along. I’ll say ‘yes,’ no matter what. And he called me for ‘Into the Woods,’ so I went and I did that.”

Now, Peters is in “Old Friends,” which began as a gala put on by producer Cameron Mackintosh in London. Its success led to a four-month run in the West End, before heading to Los Angeles and finally to Broadway.

In the show, the actress croons heart-wrenching numbers she’s known for, like “Losing My Mind” and “Send in the Clowns.”

“As I get older all the lyrics really seem to have a lot more meaning for me,” she said.

But Peters has also thrown us some Sondheim curveballs. For “Into the Woods,” the fairytale musical which has evolved into a cherished classic, Peters doesn’t sing “Children Will Listen” as the Witch — she becomes young Little Red Riding Hood instead.

Her tune “I Know Things Now” is about being chased by the Big Bad Wolf.

“I went, ‘What have I done?! I’m singing a song a child sings, and now I’m an adult talking about . . . is this like a MeToo movement song?!’,” she said. “So I figured out how to do it.”

In an, erm, less innocent moment, Peters hilariously takes on Mazeppa, the “bump it with a trumpet” stripper from “Gypsy,” in “You Got To Get A Gimmick.”

Actually, the actress plays the brass instrument so well that some of her friends thought the music was piped in.

“So, I’ve gotta be a little sloppy with it,” she said.

Peters has a busy summer ahead. “Old Friends” runs through June 15. Go see it.

Also a film star, having played opposite Steve Martin in “The Jerk,” she met up with me the same week she did a day of shooting for “A Real Pain” Oscar nominee Jesse Eisenberg’s upcoming musical-comedy movie for A24, which also features Julianne Moore and Paul Giamatti.

She’s an activist, too. Her  long-running animal adoption charity event, Broadway Barks, takes place in Shubert Alley on July 12. 

And then she packs her bags and tours her concert all around the country before heading to Australia in the fall.

Peters is the picture of a dependable showbiz workaholic, and arrives at the theater every day almost four hours before curtain. 

“I have to practice my trumpet,” she said.