Andrea McArdle, famous for being a Broadway belter at age 12, swears she’s going to write a book. “But I need to wait for a few people to go to a happier place,” she says.

I, for one, can’t wait to read the book. If McArdle’s opening-night at the Rrazz Room on Thursday is any indication, that is going to be one entertaining autobiography. But somehow she’s got to make that story sing. Without that voice, we’d only be getting part of the story.

McArdle’s short run (she concludes on Saturday) offers a little slice of heaven for the show tune enthusiast. Oh, hell, it’s pride week so let’s be frank – she’s making the show queens squeal with delight. Squeal, squeal.

Gorgeous at 44, McArdle took the stage in a tailored white pant suit and black tee. If she’s been through the wars – and she really has – she sure doesn’t look it. And her voice, which was compared to Merman in her pre-teens, still has that clarion ring, with a belt to keep the sun coming out for many tomorrows yet to come.

She gave a pretty good indication what this show would be like with her first song, a little tribute to Judy Garland with “Zing! Went the Strings of My Heart.” She dipped into her own Broadway songbook next with “NYC,” a song from her star-making show, Annie. It’s a song she didn’t get to sing in the show, though she can be seen singing a bit of it in the made-for-TV movie version.

One thing that’s immediately apparent about McArdle: she’s an extraordinarily energetic performer, at ease with the crowd and herself. She’s also far from a has-been former kid star. She’s got vitality to spare with a unique voice that can find a smooth ’70s groove on “Superstar” or blast the Broadway drama on “I Dreamed a Dream” from Les Miserables.

She revs up Sondheim’s “Everybody Says Don’t” and then cools down for a sexy solo take on another Sondheim tune, “You Could Drive a Person Crazy.” Yes, she sings “Tomorrow,” a song she’s been rattling the rafters with for 28 years now, and on Thursday, she wasn’t going to go for the money notes until her pianist, the one-and-only Seth Rudetsky, intervened and said you can’t just leave the audience hanging. So they backed up and McArdle, who claimed earlier in the show to be suffering from a lengthy afternoon rehearsal, showed us why Annie, one of the last Broadway shows not to use body microphones, didn’t need no stinking amplification.

Having Rudetsky on piano guarantees several things: expert musicianship and an even more expert sense of humor. He added harmony vocals here and there (most notably on “Beauty and the Beast” from the Disney show of the same name, which McArdle starred in), but he also teases stories out of her and adds his own inimitable flair, usually in the form of hilarious facial expressions. In addition, Rudetsky provides back-up when McArdle forgets the words, as she did on “Some People.”

Even when she’s not singing, McArdle is a delight. She tells stories on herself, like spilling M&Ms all over the stage at Les Miserables and getting reported to the union for her carelessness (but the death scene was tremendous!). Some young performer challenges her and she retorts: “Hello, ever been on Broadway before you could vote? I didn’t think so.”

Comparing the experience of being in a happy-perky show like Annie to a depressing show like Les Miz, McArdle swears the death and angst is easier: “Sing, die. Sing, die. Trust me.”

Speaking of Les Miz, McArdle brought her nearly 20-year-old daughter, Alexis Kalehoff, to the stage to sing “On My Own.” Now, it might be cringe-worthy to indulge a mother’s need to share her daughter’s talents with the world. But Kalehoff is a Broadway veteran and, in fact, was in Les Miz as young Cosette at age 7, which beats her mother’s arrival on Broadway by five years. Alexis is, like her mother, a powerhouse singer and even sounds, in certain parts of her voice, like a young McArdle. I wanted the mother-daughter duo to sing together, but alas, we’ll have to wait for that number.

Leaving her audience with “Over the Rainbow,” McArdle could have performed all night and still not quite satisfied the hungry opening-night audience. They lapped up stories about Carol Channing chiding a 20something McArdle for dissing “Tomorrow” (“Poor Leslie[Uggams] is still waiting for a signature song,” Channing said) and little dropped details like the youngest orphan in the London production of Annie happened to be Catherine Zeta-Jones.

It’s all good stuff. As for the rest of it, we’ll just have to read the book.

Andrea McArdle in concert through Saturday, June 28 at the Rrazz Room in the Nikko Hotel, 222 Mason St., San Francisco. Tickets are $40 (Friday) and $42.50 (Saturday). Call 866-468-3399 or visit www.TheRrazzRoom.com for information.

Here’s McArdle performing “Maybe” from Annie on an R Family cruise.

And how here’s Rudetsky deconstructing McArdle’s voice circa Jerry’s Girls in 1984.