The newly engaged Britney Spears and Jason Trawick hit Las Vegas Friday night (Dec. 16) to celebrate his 40th birthday at Planet Hollywood. While some eyes were on the decadent two-tier black and white red-velvet birthday cake that Spears surprised her hubby-to-be with, most eyes were on Brit’s new bling!

Spears has been beaming about her engagement since Trawick popped the question on December 15. The following day, Spears updated her Facebook relationship status from “In a relationship” to “Engaged.”

“Still glowing!” the singer tweeted on Friday afternoon, just hours before announcing her exciting news of her “one gift I’ve been waiting for.”

“About to jump on a plane to Planet Hollywood in Vegas. Throwing a Bday Party for Jason at Chateau Night Club. So fun. Xxoo,” she continued in her tweet.

Upon their arrival in Vegas, Spears and her fiance were reportedly hand-in-hand throughout the evening, which began at the Sugar Factory’s Chocolate Lounge. The lovebirds then were on their way to the Chateau Nightclub to celebrate both Trawick’s birthday and their new engagement.

Spears and Trawick were in the company of 30 of their closest friends and family members, who dined on salmon and various pizzas for dinner. Desserts consisted of chocolate pizza, cupcakes, gumdrops and other delicious sweets.

Spears met Trawick when he was an agent for William Morris Endeavor Entertainment. Up until that point, Trawick had also worked closely with some other famous faces in the entertainment industry, including Taylor Swift, Heidi Klum, Paris Hilton and Hilary Duff.

The two took their relationship to a personal level in 2009 when they started dating and Trawick ended his business relations with the star. Among other things, Trawick helped mend the estranged relationships between Spears and her parents, as well as landed her the role on the hit TV show ‘How I Met Your Mother.’

Congrats to Spears and Trawick from all of us here at PopCrush!