“It was an old-school and very glamorous Hollywood event,” a source tells PEOPLE of Paltrow and fiancé Brad Falchuk’s celebration, adding that “even with all the celebs, it wasn’t a stuffy party.”
“Instead, lots of candles and fragrant flowers created a romantic atmosphere. It felt intimate and very special. You could tell that all guests very much love the couple,” the source continues.
Guests at Paltrow and Falchuk’s Los Angeles bash included Jennifer Aniston, Cameron Diaz and her husband Benji Madden, Julia Roberts, Demi Moore, Reese Witherspoon and Kate Hudson, who’s currently expecting a daughter with boyfriend Danny Fujikawa.
Upon walking into the engagement party on Saturday, which was held inside the ballroom at the Los Angeles Theatre on Saturday, “guests were greeted with cocktails,” the insider tells PEOPLE.
Describing the event’s festivities, the source added that “several guests spoke and toasted the couple” and there “was a live band and dancing.”
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Additionally, the marquee of the Los Angeles Theatre was outfitted with a sweet custom message: “BF loves GP.”
Giving a shout out to their “favorite couple,” Tobey Maguire‘s estranged wife Jen Meyer shared a selfie with Sara Foster on the duo’s way to the event. “Saturday night and we’re all off to celebrate our favorite couple,” she wrote in the caption.
Giancarlo Giammetti of Valentino also sent the couple his love.
“These two beauties inside and out get engaged tomorrow!!!” he captioned a photo of the couple. “All my best wishes my dear @gwynethpaltrowand @bradfalchuk love you and miss not to be there with you!!!”
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The star-studded event took place shortly after Paltrow returned from a bachelorette getaway in Cabo, Mexico, at the not-yet-open Four Seasons Costa Palmas resort. A source previously told PEOPLE that Paltrow, who brought along a few of her closest girlfriends, enjoyed a schedule packed with fun outings.
“Gwyneth arrived in Cabo Wednesday with a group of girlfriends, including Stella McCartney, for her bachelorette party,” the source said. “She looked ecstatic. They have many fun activities planned, including pool time, spa and fun dinners.”
After three years of dating, Paltrow and Falchuk announced their engagement in January with a sweet shot on the cover of Goop Magazine’s Sex & Love issue. The mother of two debuted her massive sapphire engagement ring that same month at the Producers Guild Awards.
Paltrow previously opened up about her upcoming nuptials, telling PEOPLE, “I’m excited about everything!”
“I’ve never had a wedding before. [Paltrow and ex-husband Chris Martin eloped in 2003.] So even though I’m 45, I sort of feel like a 21-year-old,” she added.