The new Voice mentor, 23, threw back to her Hannah Montana days in a long brunette wing. She wore a jean dress with heart-shaped prints, knee-length socks and colorful plastic jewelry.
The BFFs had a dance party, sipped on pumpkin-spice lattes and caught up with each another. "I didn't see you, like, all summer," Fallon's blonde-haired Sara said.
"I know!" Cyrus as Becky said. "First, I was at theater camp. Then I had to go on a family vacation to the Grand Canyon. Ew! It was so lame. It's just a big dumb hole in the ground and it doesn't even have Wi-Fi. I'm actually glad to get back to school."
The gal pals' basement reunion didn't last long. Becky's nosy dad interrupted and tried to fit in. "Ew!" Sara screamed. "Shut up! Get lost!"
Cyrus isn't the only celeb to get her "Ew!" on during the NBC late-night show. Other stars who've rubbed shoulders with Sara include Channing Tatum, Seth Rogen, Zac Efron, Ariana Grande, Lindsay Lohan, Taylor Swift and Emma Stone.
Watch the funny video above!
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