Amy Winehouse crammed a lot into 27 years. The multiple Grammy winner lived fast, died young, and left a tiny cache of unreleased music that reaches retail today in the form of her career-spanning posthumous collection Lioness: Hidden Treasures.

While many people remember the singer-songwriter less for her prodigious talent as a retro-soul/bebop chanteuse than as the disheveled figure she became—a pop casualty bumbling around central London with her coke boogers on conspicuous display—Winehouse’s fans reacted to her death from alcohol poisoning in July by racing to purchase her two studio LPs. It seemed as if even before the body was cold, both Winehouse’s 2003 debut, Frank, and her 2006 masterwork, Back to Black, had catapulted to the top of the pop charts around the world.

To be sure, Winehouse’s faithful will make up the audience most likely to be thrilled by Lioness’s 45 minutes of accumulated odds and ends, demo-tape outtakes, and postmortem audio doctoring—a collection the album’s primary producer, Salaam Remi, nonetheless insists is not going to lead to a “Tupac situation” with the endless trot-out of after-death releases in the future.

But Lioness holds many unexpected pleasures even for people who do not self-identify as Winehouse completists. In its own halting way, the album charts the singer’s progress from her tenuous early incarnation as an eager-to-please teenager all the way to the slurred enunciation and ravaged grandeur of her penultimate work. Moreover, three or four of the songs throw Winehouse’s staggering potential into stark relief, indicating some of what she might have accomplished had she been able to outrun or outlast her personal demons.

We’ve heard some of this material before. Notably, the acoustic 2004 cover of the Shirelles’ “Will You Still Love Me Tomorrow” (which previously appeared on the soundtrack for Bridget Jones: The Edge of Reason), and one of Winehouse's final professional recordings, “Body and Soul,” a cover of the jazz standard with Tony Bennett—you could easily imagine it playing in a department store during the Christmas rush—that can also be heard on the crooner’s latest album, Duets II.

Meanwhile, other songs on Lioness simply feel like stuff we’ve heard before. To wit: despite some nimble scatting on the track, Winehouse’s highly caffeinated cover of “The Girl From Ipanema” comes off pretty much exactly how you’d expect a bossa nova smash reworked for a trip-hop audience by a neo-Motown diva to sound.

But consecutive listens to Lioness beget a central question: where would fellow Brit retro-revisionists such as Duffy or Adele be without Winehouse’s renovation of the genre?

Her cover of Ruby & the Romantics’ “Halftime” swings with the kind of percolating Nu-Soul boom bap that put Winehouse on the map in the first place; it’s the kind of song that inspired those other singers to follow in the jazzy white-girl R&B template she created. The Remi-produced “Like Smoke” not only frames Winehouse’s powerful contralto with a lush, Motown-worthy wall of sound, it provides the druggy Cockney diva with something denied to her in life: a dream “collabo” with Queens rapper Nas. Her favorite MC (and the inspiration for her hit “Me and Mr. Jones”), Nas returns the compliment by spitting the rhyme “You colder than penguin pussy”—one of Winehouse’s preferred insults—on the track.

And like much of her best material, “Best Friends, Right” pairs Winehouse’s singular vocal phrasing with confessional vocals that highlight the coquettish loyalty she was known to have required from those close to her. Or just call it drug-enabling behavior: “Someday I’ll buy the Rizzla, so you get the 'dro,” she sings.

Lioness closes with the album’s one unquestionable hidden treasure: a version of the oft-covered Leon Russell paean to regret, “A Song for You,” which was also famously sung by her idol Donny Hathaway in 1971. Winehouse laid down the track in her attic studio in 2009, at the apogee of her hard-partying ways. Whether compelled by her already far-gone physical dissolution or her continuing grief over having lost the love of her life, ex-husband Blake Civil-Fielder, Winehouse reportedly wept as she sang. “It’s as if she was literally singing about herself,” Remi recently recalled to Rolling Stone. “She was really putting herself into it.”

Over a backing track that channels the stately gloom of Portishead and late Isaac Hayes, Winehouse sounds almost Edith Piaf-like. Her emotional anguish is palpable enough to make you want to give her a hug through the speakers. And as such, “A Song for You” provides a haunting coda to the performer’s career.

“And when my life is over,” Winehouse sings at its close, “remember when we were together/We were alone and I was singing this song for you.”