She was leaving her interview with E!'s Ryan Seacrest when she spotted Streep on the carpet behind her and completely freaked out, nearly falling and asking "Can I meet you?"
In the exclusive Voice featurette above, Clarkson recalls that moment.
"I think everyone knows this answer," she says. "Someone who makes me starstruck—cuz I meet a lot of people, but boy, I just made an absolute ass of myself in front of Meryl Streep. Yep. And you know what? I don't care. I don't care."