Both Queen and Worker B

“I’m just trying to stretch 15 minutes out to 20 minutes,” Toni Braxton says of her fame. The sultry soul singer has an endearing way of underplaying her enormous success, which long ago surpassed the 15-minute mark.

Braxton is one of the hottest female artists in the competitive pop galaxy. Her 1993 debut album (“Toni Braxton”) has sold an astonishing 10 million copies worldwide, and the follow-up album (“Secrets”), released in June, shattered any notions of a sophomore jinx.

“Secrets” sales have surpassed 2 million in the United States and continue briskly. With the 28-year-old vocalist having recently embarked on a tour with saxophonist Kenny G (the co-headliners appear at the Pond of Anaheim tonight), the album figures to have plenty of commercial life left.

Nevertheless, Braxton isn’t one to rest on her laurels, and she’s not about to take her good fortune for granted. Despite her hit albums and 10 Top 10 singles, she approaches her career in a refreshingly pragmatic and realistic manner.

“I have to work really, really hard when [the commercial success is] happening, because it may never happen again,” she said in a recent phone interview from a San Jose tour stop. “I feel very fortunate. . . . So many artists have had successful first albums, and I see them on these compilation CDs, and I go, ‘Wow. What ever happened to them?’ ”

Braxton’s success wasn’t quite overnight. She signed to Arista Records in 1990 as part of the Braxtons, a vocal quartet with three of her sisters. The group’s first single bombed, but vaunted R&B; producers Antonio “L.A.” Reid and Kenny “Babyface” Edmonds were so impressed with Braxton’s low, sensuous vocals--to say nothing of her fetching good looks--that they signed her to their LaFace Records label as a solo artist.

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It didn’t take long for Braxton to strike gold. Featured on the soundtrack album to the 1992 Eddie Murphy film “Boomerang,” “Give U My Heart” (a duet with Babyface) and “Love Shoulda Brought You Home” were both breakthrough hit singles for the up-and-coming vocalist.

But it was her debut album that established Braxton as a soulful chanteuse specializing in mournful, romantic ballads. “Best Friend,” an autobiographical song that she co-wrote for the album, is typically Braxton. It’s about a difficult breakup with a boyfriend that was made worse when her best friend immediately started dating him. Braxton believes her ability to convincingly convey the emotions involved in real romantic experience is a key reason her songs prove so enticing.

“When I wrote the song, it was therapeutic,” she says of “Best Friend.” “Sometimes when you write about things in your life, it makes you feel so much better when you share it with other people and let them know that it’s OK and that you’ve gone through the same thing they’ve gone through. That makes it real to them. It’s like, ‘She’s like us.’ It’s important to me that I don’t have this glass wall between me and my fans.”

The new album contains its share of moody ballads. But there are also tracks that place Braxton in a new light. “Come On Over Here” adds an upbeat dimension to her repertoire. “You’re Makin Me High,” the album’s funky first single, is an unabashedly erotic song capable of raising body temperatures. Braxton--who, as a girl in Severn, Md., wasn’t even allowed by her parents to listen to secular music until she was about 13--says she was initially uncomfortable singing some of the sexually charged lines in the latter song, which was written by Babyface and Bryce Wilson, her current beau.

“I gave my dad the CD single. He didn’t say anything for a few days. [Finally] I said, ‘What do you think about the song?’ . . . He said, ‘Well, it has a very nice beat.’ That’s all he said. I wasn’t going to ask anything else!” she said with a laugh.

Though she is known for her bewitching sexuality and seductive stage attire, Braxton in an interview comes across as appealingly down to earth. She says people are often surprised when they meet her.

“Most people don’t expect me to be as short as I am [5 foot 2],” she says. “They expect 5 foot 8 and bodacious! A lot of people say I look much younger in person, and that I look like a little kid. I have the young guys going, ‘How you doin’? Did anyone ever tell you look like Toni Braxton?’ ‘I go, ‘Oh, sometimes.’ ”

* Toni Braxton and Kenny G perform tonight at the Pond, 2695 Katella Ave., Anaheim. $30-$55. 8 p.m. (714) 704-2500.