04/16/2013 at 06:00 PM EDT
When it comes to diets, country superstar Trisha Yearwood has been there, done that.
"I don't think you can name one diet I haven't done. I'm that girl who buys every magazine where somebody's lost 30 lbs.," the Grammy-winning singer tells PEOPLE in this week's cover story.
"I guess a part of me didn't want to hear that it's just really hard work!"
Lately, however, her hard work has paid off. Yearwood, 48, is now showing off her brand new body
after dropping 30 lbs. in the past four months.
"I designed my own plan that's low-fat, low-sugar 90 percent of the time," says the country star.
The other 10 percent of the time, she indulges in her favorite foods – but in moderation and with the motivation to work it off the next day.
"There's no way you never fall off the wagon," says the best-selling cookbook author, whose go-to workout is taking Zumba classes at least three times a week. "I fell in love with it!"
Down from a "tight size 14" to a slim size 10, the star of Food Network's Trisha's Southern Kitchen
is feeling fearless.
"I have a strength I never had before," she says. "I feel like I can do anything."
For all the details on how Trisha got her new body – including a peek at the inspiration board she hangs in her closet! – pick up this week's issue of PEOPLE, on newsstands Friday