Amy Tan's novels are powerful portraits of family struggles, particularly between Chinese mothers and American daughters. So it's certainly surprising to see her name on the calendar of Yoshi's in San Francisco, where she'll introduce Parisian singing sensation Pascal Toussaint this Sunday.

"I don't know why I've done this," she says, seated in her Sausalito home before turning to Toussaint. "Maybe in another life you were my son or my daughter," she says with a chuckle. Indeed, Tan exudes a maternal energy around her discovery, even gently scolding Toussaint about forgetting his cell phone again. "But this talent, this voice, this emotion needs to be heard," she tells me, "and it would be a tragedy if it weren't."

"Tragedy" doesn't seem hyperbolic after hearing Toussaint's voice, a gorgeously high, piercing intonation much like a female mezzo-soprano, with a range spanning four octaves. Whether singing "Je Suis Malade" or "My Funny Valentine," Toussaint recalls a myriad of jazz greats—Nina Simone, Jimmy Scott, Josette Daydé—while exhibiting his wholly singular expression.

It was his rendition of "I Loves You Porgy" that struck Tan in a Paris cabaret last summer. "I thought, 'Her voice is wonderful,'" she remembers, "and then after a while, I realized it was not a woman, it was a man. Then I stalked him."

Tan made contact with Toussaint via MySpace with an extremely gushing note. "Oh, wow," Toussaint says, using his hands to describe the long message. "I just thought, 'That's amazing.' I didn't know my voice had this power."

Although 29, the petite Toussaint could pass for half that, in part because of his gentle, high-pitched voice. The result of a rare congenital anomaly, his voice did not break at puberty. Toussaint is the rare countertenor, reaching the highest registers without using falsetto. This only accentuates his palpable charisma, an alluring androgyny highlighted by a handsome face and beautiful braids.

"My whole life people made me feel I was special, even my parents," says Toussaint, who studied at the Conservatoire in Paris. His choir-director father has always been supportive, yet strict. "He used to tell me, 'You have the voice, but talent is nothing without work.'"

Tan can relate, with 15 years of classical piano training as a girl. "Mother and father had dreams that I'd be a performer, but I had a terrible first recital, so I was never going to do public performance," she remembers. But Tan does sing for the Rock Bottom Remainders, a rock 'n' roll collective of published writers that includes Maya Angelou and Stephen King. "It's amazing that I'm in this band making a fool of myself," she says, "because I have no vocal talent." Back in 2008, the lover of opera also co-write one, based on her novel The Bonesetter's Daughter. Yet her current musical focus remains clear.

"I'm his Chinese Godmother," she says with a smile. "If you provide the opportunity, what should happen, will happen. I never would have predicted that what happened to me would happen."

Although he's now fielding interest from record labels and music festivals, Toussaint remains grounded. "My big dream is to perform at Madison Square Garden," he says, "but as long as I keep on singing, I'm good."

A budding composer, Toussaint's favorite original song in his repertoire is "The First Time." He explains: "It's about the first time you see someone, and you just think 'She's the one' or 'He's the one.' You can't even speak, you can't even think, and you don't even know who you are anymore, you're just like, 'Wow.'"

Is it about anyone in particular?

He laughs intriguingly, then gives me a sly little smile. "You're too curious."

A star is born, folks.

Pascal Toussaint and Amy Tan appear on Wednesday, Feb. 24, at 142 Throckmorton Theatre (142 Throckmorton Ave., Mill Valley. 7:30pm. $16–$20. 415.383.9600) and on Sunday, Feb. 28, at Yoshi's (1330 Fillmore St., San Francisco. 8pm. $25. 415.655.5600). For more info, see www.pascaltoussaintmusic.com

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