Superstar Carrie Underwood's luscious blonde locks are nearly as stunning as her powerful vocals, but the American Idol winner's hair wasn't always her pride and joy.

In an interview with Huffington Post, the Underwood shares the one hairdo that haunts her to this day.

"Oh, hair! I tend to have a natural curl in my hair, anyway, but not a whole lot,” she says. “When I was in college, I would put a lot of product in my hair and force it to be curly. And I definitely did that on my first Idol audition! I call it my ‘crunchy’ hair. That, I might like to undo if I could.”

While looking at old photographs causes the star a bit of embarrassment, nowadays she's very content with her hairstyle, beauty routine and health. As a global ambassador for Almay cosmetics, she knows a thing or two about ideal beauty routines.

Her most surprising beauty secret? Drinking water— lots and lots of it!

"Water is something that is so important, not just for a beauty routine but for keeping yourself energized and making sure your body is working the way that it should," Underwood insists. "I'm always drinking water — SOOO much water!"

While she claims she can finish her signature makeup and hair style in less than 15 minutes if needed, Underwood prefers to spend some extra time on her beauty regimen. “I mean, I kind of like taking my time in the morning,” she shares. “I’m waking up and trying to get myself going for the rest of the day. But I can be ready, start to finish in about 15 minutes — hair, makeup, everything — if I have to be, but I’d really rather not."

See Pics of Carrie Underwood and More as Kids

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