From left: Sofia Vergara, Wiz Khalifa and Amber Rose
Splash News Online; Vivien Killilea/Getty
03/20/2014 AT 06:00 AM EDT
Her fiancé may be the king of condiments, but sometimes Sofia Vergara
just craves a good steak.
The Modern Family
star celebrated with a group of 24 at the launch of her newest campaign for Head & Shoulders Shampoo Monday night at STK Los Angeles.
"She was in great spirits, talking and posing for photos with everyone," a source tells PEOPLE. "She came directly after set and even showed the commercial to her guests during the party."
Across the restaurant, newlyweds Wiz Khalifa and Amber Rose
were spotted toasting a friend's birthday.
Dressed casually in a jeans, T-shirt and leather jacket, the rapper and his wife sipped on the restaurant's signature Strawberry Cobbler cocktail while tucking into beef tartare, romaine salad and filet of steak.
"They were sitting next to each other and were very loving, chatting and holding hands," says the source. "They were both super nice to the staff."