The singer, rapper and flautist channeled a boisterous if profane life coach while performing for a sold-out audience

Lizzo’s sold-out Sunday concert at Express Live outdoors could have doubled as a mass self-empowerment seminar.

On a thunderous “Soulmate,” the Detroit-born, Houston-raised, Minneapolis-based rapper, singer and flautist did more than trumpet her own self-worth — “I’ma marry me one day,” she sang with typical bravado — she also challenged the heavily female audience to see theirs, as well. “Look up in the mirror like, ‘Damn she’s the one,’” she crowed.

Elsewhere, Lizzo, performing behind her breakout third album, Cuz I Love You (Nice Life/Atlantic), which debuted at No. 6 on the Billboard 200 following its release earlier this year, turned out a stream of fearless, largely up-tempo songs on which she refused to be defined by her exes, society’s expectations or even her own waistline. “Slow songs, they for skinny hoes/Can’t move all of this here to one of those,” she rapped at the onset of the slinky “Tempo,” one of a handful of tunes that championed body positivity.

Between songs, Lizzo, born Melissa Jefferson, carried on a similar conversation with the audience, reminding attendees that, among other things, the view of love on display in the 1996 film “Jerry Maguire” is flawed. “No, you complement me, because I’m already complete, bitch,” she offered as a modern rejoinder to Tom Cruise’s “you complete me” speech. She also repeatedly stumped for the “big girls” in the crowd. “You are beautiful. You are worthy,” she beamed. “You’re all of that and a bag of chips. And you can eat that bag of chips, too, bitch.”

At another point, Lizzo, who frequently channeled a boisterous if profane life coach, said she wanted to take a moment to connect with the crowd. She followed by summoning all of the “love energy” the universe could muster. “Now put all that love energy right here,” she said, gesturing toward her heart. “Put it between your titties.”

At times, the combination of messaging and music, as well as the obvious adoration between audience and performer, made the evening feel less like a concert than an intimate sleepover, minus the late-night toilet-papering of a crush’s house.

Lizzo was joined for the nearly 80-minute concert by friend and DJ Sophia Eres, a quartet of backup dancers, affectionately known as “the Big Girls,” as well as Sasha Flute, the name Lizzo bestowed on her famed instrument, which even has its own massively popular Instagram account (@sashabefluting), putting it in the same weight class as B.B. King’s guitar, Lucille, and Willie Nelson’s Trigger, neither of which could be similarly classified as a social media influencer. Even here, Sasha appeared only in cameo form — a fitting move for an instrument that follows precisely zero people on Instagram.

Not that Lizzo needed any assistance, however. The musician shape-shifted effortlessly throughout the evening, alternating between shimmying EDM siren (“Phone”), rap queen (“Truth Hurts”) and, on songs such as a shattered “Cuz I Love You,” tortured blueswoman, dropping to her knees outside of an ex’s house, tears falling as steadily as the rain.

It was an impressive display from someone who was largely cast as a flute-playing rapper during a decade spent in the Minneapolis hip-hop scene — and miles removed from the (slightly) less braggadocios youngster who turned up on 2013’s “Wat U Mean,” rapping, “Normally, I don’t like to toot my own horn.”

Now, Lizzo will not only toot her own horn, but she’ll lean into it, carrying herself with a confidence that suggests she’s ingested the very-Prince-like advice once delivered to her by none other than Prince: “Be eternal.”

The singer managed just that at several points throughout the concert, none more so than on a chill-inducing “Jerome,” a blues-indebted slow burner on which Lizzo summoned the likes of Ruth Brown and Koko Taylor, growling, shouting and emitting wordless moans between laugh-out-loud lines directed at a man the singer described as “a scrub” in introduction. “I’m sorry, 2 a.m. photos with smileys and hearts/Ain’t the way to my juicy parts,” Lizzo scolded the ne’er-do-well, chiding him time and again to “come back when you’re grown.”

It’s a transformation the musician knows well.