12/15/2009 AT 6:00 PM ET
Vanessa Hudgens got a big surprise Monday night – a group of about 100 friends gathered at East Restaurant & Lounge in Hollywood to celebrate her 21th birthday.
Hudgens, decked out in a black mini dress with lace cut-out arms, arrived with beau Zac Efron in a chauffeured Audi Q7, and “when she walked in was completely surprised!” says a guest at the party.
Efron gave a heartfelt speech – wishing Hudgens a very happy birthday and encouraging guests to have a fun night. Partygoers noshed on East signature dishes including the crab cakes and scallops on the half shell while mingling and dancing.
Hudgen’s red velvet birthday cake was presented to her about an hour into the party. “She seemed overjoyed and grateful for the whole experience,” says the guest.
“Zac and Vanessa were adorable together,” says another guest. “They were smiling at each other and laughing and are really sweet to each other. Great couple.”