Kesha is making one kind of remarkable recovery. During her first post-rehab performance at Petty Fest on Thursday (April 3), the once troubled singer performed a cover of Tom Petty's hit "Free Fallin.'"

Her voice is as sharp as ever, and even though the entire crowd was singing along, she soared and dipped over the song's ironic lyrics. The 27-year-old is turning over a new leaf, no longer trapped by the machinations of the music industry. You forget that Kesha Rose, as she's now known, is a terrific vocalist. When she's plagued with pressures to use autotune, her raw talent gets muddled.

"She's a good girl. She loves her momma," she coos on the first verse. In reality, it was her mom who came to her defense when the singer first landed in rehab, taking out her anger on pop producer Dr. Luke and blaming him for her daughter's struggles. "Dr. Luke told a friend of ours he thought she looked like a refrigerator on her latest video, and could she please try to control her weight," Pebe Sebert had blasted in January in an interview with People. "After she went on a 14-day juice cleanse, he said, 'Thank God you finally got rid of the weight! We've all been talking about it!' So she felt like she couldn't trust anyone."

But that is a thing of the past now. Kesha looks healthier than she has in a very, very long time. Good for her, and here's to a bright future!

As we previously reported, the "Die Young" performer is already hard at work on new music, enlisting the likes of Zedd for her Warrior followup. Known for his own chart-topping solo work, he's also collaborated with Lady Gaga (on her severely underrated ARTPOP set) and Justin Bieber (co-producing "Beauty And The Beat" with Max Martin).

Check out Kesha's performance: