Gabourey Sidibe Worked at a Phone-Sex Company for 3 Years Before Her Big Break: ‘My Acting School Was on the Phone’

Gabourey Sidibe got her acting chops in a rather unconventional manner!

Prior to scoring her breakthrough role in 2009’s Precious, the actress worked at a phone-sex company.

“I was actually pretty good at it,” Sidibe, 33, tells PEOPLE of the phone-sex gig, which she did for three years, fielding calls for two months before moving up in the business. “I did it for two months before I was promoted.”

In addition to opening up about her weight-loss surgery, the actress chronicles her life before she became famous in her new book This Is Just My Face, out in May. The New York City native got the job in her early twenties after she dropped out of college to focus on her mental health and attend therapy, having battled depression, anxiety and bulimia since she was a teenager. Though she promptly quit the job when she was cast in Precious at the age of 24, she insists her previous line of work prepped her for an acting career.

“I knew that when people were asking me, ‘So have you had any acting training?’ my acting school was on the phone, pretending to be some super-young 21-year-old college girl named Melody. I know that was my acting!” Sidibe says. “But I felt too stupid to say it.”

Still, she says she was nervous about sharing that aspect of her pre-fame life when she first broke onto the scene.

“I was really nervous about it when I was 25; I was really, really nervous about it when Precious was coming out,” says Sidibe, who went on to earn an Oscar nod for her role in the film. “The whole Oscar run, all of it — I was becoming an actor, becoming a person that people were interested in and looking at and judging, so I didn’t want what I did for work .”

Indeed, the Empire star was concerned about how people would react to taboo occupation — not that she was ashamed of it.

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“I wasn’t just some phone whore,” she says. “Remember when Diablo Cody‘s Juno was coming out, and people were like, ‘She’s an ex-stripper‘? Yeah, but she wrote this dope film. Can you not? Because that’s just one part of her life.”

While the star hasn’t worked in phone sex for almost a decade, she recently experienced a full-circle moment.

“The last photo shoot for my book was in the same office building that I did phone sex for three years in!” she says. “It’s so crazy! My editor came in, and I was like, ‘You’re not going to f—ing believe it: We’re on the third floor, but the office was on the tenth floor!’ So we went to the tenth floor to see how it changed. The place went out of business the second I wasn’t there anymore. It was so weird; all of my senses came alive. I could smell the HR room, the coffee over there … The last thing I did for the book was go right back to where I was a f—ing phone hoe!”

For more on Gabourey Sidibe and an exclusive excerpt from her new memoir This Is Just My Face: Try Not to Stare, pick up the new issue of PEOPLE, on newsstands everywhere Friday.

Sidibe’s debut memoir, This Is Just My Face: Try Not to Stare, hits bookstores in May.