Joni Mitchell Jokes She 'Didn't Sound Too Bad' After Surprise Festival Set, Her First Show in Decades

Joni Mitchell is back!

The legendary singer-songwriter made a surprise appearance at the Newport Folk Festival Sunday night, sharing the stage with Brandi Carlile, Marcus Mumford and more in what was her first full set performance in more than 20 years.

Mitchell, 78, delighted the crowd with 13 songs, including classics like "A Case of You," "Both Sides Now" and "Big Yellow Taxi" — songs she feared she may never sing again after she suffered a near-fatal brain aneurysm in 2015.

"I've never been nervous about being in front of an audience," Mitchell later told CBS News. "But I want it to be good. And I wasn't sure I could be. But I didn't sound too bad tonight!"

The performance marked her first full set since she headlined a benefit concert in Los Angeles in 2002, and her first public performance since 2013, when she sang briefly at a concert tribute in Toronto, according to her website.

The Blue singer told CBS News that after her aneurysm, she had to teach herself to play the guitar again, among other skills that had to be relearned.

"I'm learning," she said. "I'm looking at videos that are on the net to see where I put my fingers, you know. It's amazing what an aneurysm knocks out – how to get out of chair! You don't know how to get out of a bed. You have to learn all these things by rote again. I was into water ballet as a kid, and I forgot how to do the breaststroke. Every time I tried it, I just about drowned, you know?. So, a lot of going back to infancy almost. You have to relearn everything."

Earlier this year, some of music's biggest names came together to honor Mitchell as the MusiCares Person of the Year in Las Vegas.

For well over three hours, guests wined and dined while listening to a bevy of iconic and modern-day artists cover Mitchell's songs. Some musicians were excited to simply be in the same room as the "River" singer, whereas others shared personal stories of how Mitchell influenced them.

"We are all better artists because of the lines you dared to cross," Billy Porter said ahead of a moving performance of "Both Sides Now." "Joni Mitchell, you are marvelous."

In addition to performances by Brandi Carlile, Beck, John Legend, Mickey Guyton, and more, A-list artists also sent in video tributes. Lionel Richie spoke of buying a house across from Mitchell's and plotting to casually bump into her one day (it never worked, but she did eventually invite him over).

Elton John said in a vignette, "You've influenced me so much with your chord changes and ability to surprise and delve further into songwriting. Not many people dared to do that, but you did."

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Upon receiving her award at the MGM Grand, Mitchell, who walked with a cane, thanked the performers and even threw in some humor.

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"That was such an incredible evening for me. To hear my music performed so well by everyone that was on stage, I can retire now and just let other people do it," she joked.

Reflecting on the evening, Mitchell told CBS News that having her body of work recognized felt "very rewarding."

"You know, a lot of doors were shut to me. Like the Rock 'n' Roll Hall of Fame. They kept me out of that for a long time," she said. "[But] I'm feelin' the love, yeah. It feels good! I think having a brush with death like that kind of softens people towards me!"