NEW YORK —  Christina Aguilera (search) says she was shocked when a Valentine surprise turned into a marriage proposal. The 24-year-old pop diva says music executive Jordan Bratman (search), her boyfriend of two years, popped the question at Big Sur, Calif., last Friday after recreating a romantic dinner the two had while touring India in the fall.

"It was unbelievable," Aguilera told Us Weekly (search) magazine. "Every cute thing he did, I totally thought was just a Valentine's Day surprise — he got me!"

"He sent me on a scavenger hunt," she said. "My mom used to do scavenger hunts for me when I was a kid, so it had sentimental value. Each clue was a poem — and in the final clue he proposed!"

The 26-year-old Bratman gave Aguilera a 5-carat diamond ring designed by jeweler Stephen Webster, who also made wedding bands for Madonna and Guy Richie.

"I'm finishing my album, so we haven't set a date yet," Aguilera said. "But it's definitely given me inspiration to make my best record ever."

Her hits include "What a Girl Wants," "Genie in a Bottle" and "Beautiful."