Kelly Clarkson onstage at the 2012 MuchMusic Video Awards in Toronto, Canada. Credit: O'Neill/White/

Kelly Clarkson is back and better than ever, in more ways than one!

At Sunday's MuchMusic Video Awards in Toronto, the 30-year-old singer showed off her whittled waistline in a body-conscious graphic print dress featuring black side panels, which she accessorized with a Litter bracelet. Clarkson -- who recently shed 30 pounds -- performed her latest hits, "What Doesn't Kill You (Stronger)" and "Dark Side," and mingled with 90210's Shenae Grimes, 22, backstage.

Clarkson dropped several dress sizes thanks to a five-days-a-week training schedule and a portion-control diet. "She feels better about herself than she ever has," a source recently told Us Weekly.

The Duets mentor and original American Idol enlisted the help of her boyfriend Brandon Blackstock's Tennessee-based trainer, Nora James. "I call her Chuck Nora because she is like G.I. Jane. . . hard-core," Clarkson has raved. Despite their sweat-inducing cardio and weight-lifting sessions, Clarkson says the pro "makes it fun."

Clarkson is embracing her new shape, but she's happy at any size. "What I've figured is this: As long as I'm healthy and happy, cool. I'm just me -- take it or leave it," she says. "And personally, I think I'm looking good!"