Clooney was joined by Rande Gerber and Cindy Crawford, as well as Ryan Seacrest and Maria Menounos.
George Clooney and Rande Gerber know how to throw a party!
The two pals, together with their Casamigos co-founder Mike Meldman, hosted a private Casamigos "House of Friends" dinner at TAO LA in Hollywood on Friday night, a source tells ET.
Clooney, who arrived solo just after 8 p.m., was wearing a black tee shirt and jeans. He was joined by Cindy Crawford, Ryan Seacrest and girlfriend Shayna Taylor, Elizabeth Chambers Hammer, Brooke Burke and Maria Menounos and husband Kevin Undergaro, who all took over the downstairs area of the restaurant. Amal Clooney, however, was not in attendance and stayed home with the twins, Alexander and Ella, ET's source reveals.
The source says Clooney mingled with the crowd of roughly 100 of the trio of Casamigos founders’ closest friends, who sipped specialty cocktails including the Pineapple Smoke, Casamigos Margarita and Anejo New Fashioned.
Guests noshed on the Tao Temple salad, a chef’s selection of assorted sushi, Chicken Gyoza, Filet Mignon “Tokyo” style, Perking Duck, Thai sweet and spicy shrimp, Asian green stir fry and pad Thai.
The group also celebrated Menounos’ birthday by singing "Happy Birthday" and presenting her with a cake.
Guests, including Clooney, left the party around midnight.
Earlier this week, the Ocean's Eleven star was honored with the AFI Life Achievement Award. ET caught up with Clooney and his stunning wife at the event's red carpet, where he expressed how much the award meant to him, as well as how he and Amal celebrated their twin's first birthday.
Watch the video below to hear what he shared.
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