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Cameron Diaz whipped up one heck of a 44th birthday this week, taking in a cooking class with several of her A-list friends.

The actress was joined by her husband, Benji Madden, as well as his brother Joel Madden and wife Nicole Richie at the New School of Cooking in Culver City, California, in Aug. 30. Also a part of the birthday festivities: Gwyneth Paltrow and her boyfriend Brad Falchuk.

Photos show Cam, Nicole and Gwyneth donning aprons and taking the class very seriously. Benji was dressed very casual in a baseball hat and a black Nike collared shirt.

Us Weekly says the class was trattoria-themed and the group learned how to perfect Italian food, including wild mushroom risotto, salad and tiramisu.

Cameron was also surprised with a traditional birthday cake, a yellow cake with chocolate frosting and candles. Naturally, everyone sang "Happy Birthday" to the birthday girl.

"It was great energy, super positive, laughing, just celebrating a birthday," a source told Us. "People did bring gifts, but she didn't open them. It was a really lovely birthday dinner party, just really good vibes. Nothing out of the ordinary. They stayed for around three hours."

An onlooker said the group reveled in the birthday, often raising their glasses, adding that there were "toasts and cheers and hugs and kisses."

The same day, Benji took to social media to gush about his wife, sharing a photo of them standing in the Los Angeles County Museum of Art's famous Rain Room exhibit.

"Happy Birthday to my beautiful Wife. You're my best friend and I'm so thankful for you, sometimes I just want to tell the world," he wrote, using heart emojis through much of the Instagram caption. "Generous, Kind, Compassionate, Selfless, Humble, Thoughtful, Patient and Loyal. Just a few of the qualities I would use to describe who you are, consistently, everyday. Thank you for being you, I'm a lucky guy. Here's to many more. Love you."

Gwyneth, too, gushed about her pal on social media, sharing a photo of them along with Drew Barrymore.

She wrote, "Dear @camerondiaz, before the day ends, I bid you a happy birthday, and I hit the ground with gratitude for getting to be one of the women who calls you a best friend."