Angel Olsen may have a celestial voice, but the 27-year-old former Chicagoan is hardly cherubic. The folk singer’s delicate features belie her bad mouth and staunch independence. “I recently went to New York. I felt like someone stuck an adrenaline shot in my leg,” says Olsen. “It was, like, slow the fuck down.”

Olsen is at her most assertive on her new album, Burn Your Fire for No Witness, out this month and free to stream on NPR, trading her softer solo persona for that of a commanding frontwoman. Her 11-song lineup of fuzzed-out psychedelic-pop tunes is a salient sonic departure from her stripped-down sound on albums such as Strange Cacti and Half Way Home.

Olsen’s harder sound may seem a natural fit, but it took her years to hone. After moving to Chicago from St. Louis in 2006, the singer slowly built a name for herself playing house shows and small venues like the Hideout and the Empty Bottle.

She found an early supporter in Will Oldham, the indie-folk star who often performs under the stage name Bonnie “Prince” Billy. In 2009, she joined the Babblers, a punk cover band fronted by Oldham, as well as the Cairo Gang, which served as Oldham’s backing band. “I went from never having been on tour,” she says, “to the most extreme kind of tour life ever.”

Though her two years touring with Oldham gave Olsen an inside look at the music industry, it was her 2012 sleeper hit Half Way Home—a low-fi album that melds the drama of Édith Piaf with the delicate trill of Joni Mitchell—that wrote her ticket to success. Half Way Home went viral, and Olsen landed an East Coast tour with rocker Kurt Vile and an appearance at the 2013 Pitchfork Music Festival.

The indie-pop labels came calling, and after saying no twice—she didn’t feel ready for the attention and pressure—Olsen signed with Jagjaguwar (which reps Bon Iver and Foxygen). “She’s, in the right ways, very stubborn about her vision,” says Jagjaguwar founder Darius Van Arman.

Burn Your Fire for No Witness may be a different sound, but the vibe is uniquely hers. With a full backing band, Olsen’s magnetic voice is front and center amid reverb-soaked guitars. On naked ballads like “White Fire” and “Enemy,” she is exposed, her strength and vulnerability on full display.

Despite her confidence and commitment to her DIY roots (“I don’t want to commercialize my album … No commercials and no TV shows”), Olsen, who decamped for Asheville, North Carolina, in September (“I’m happier around trees”), knows music audiences are fickle and life as a full-time musician might not last forever. But she has a pretty solid backup plan.

“If I can’t play music, maybe I can have a taco truck and become the tamale lady of the South,” she says with a laugh. “And people will be like, ‘Did you know that she used to play folk music? Now she sells tamales!’ ”

Angel Olsen just announced an additional Chicago date to her current tour—she'll play Lincoln Hall on May 4.