After having lunch together at Italian restaurant E Baldi, McPhee and Foster shared a kiss on the lips.
The 33-year-old Smash actress wore a long sweater coat with a black shirt and jeans, which she accessorized with a black backpack and sunglasses. Foster, 68, also wore sunglasses along with a blazer and jeans.
The pair reunited later that evening at an event at the Stephen Webster U.S. flagship boutique in Beverly Hills hosted by jewelry designer Stephen Webster and Los Angeles film producer Hilary Shor. Seated side by side at the intimate event, the couple dined on food by chef Alain Giraud while guests also enjoyed tequila and vodka cocktails.
Dating rumors have followed the pair for months, but McPhee recently told PEOPLE that she had “zero desire” to address them. “It’s great that they want to do that. I think it’s so amusing that people are amused by my love life,” she added.
“Here’s how I look at it: I’m not doing anything wrong, so whether people think it’s true or false, I don’t, you know, there’s nothing bad happening in my life, so people can just say whatever they want,” she demurred.
McPhee and Foster, 68, have been friends for years, first meeting on the set of American Idol when McPhee was a contestant in 2006.
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McPhee also addressed the relationship rumors in the December issue of Health, when she commented that people can “say whatever they want” about their friendship.
“We’re very close friends, and we’ve been friends for a long time,” she added. “I’m really, really fond of him, and I think he’s an incredible person. I’ve known him since I was 21 years old, you know? He produced my first single. So he’s been really good to me. People can say whatever they want.”
Rumors about David and McPhee’s relationship started in September after the Grammy-winning producer’s daughter Erin shared photos of the pair at the Grammy Museum’s third annual gala at The Novo in Los Angeles, writing in the caption, “Excited about my new step mom.” (A source close to the situation told PEOPLE at the time that the social media posts were a joke.)
In October, the two were also photographed walking arm-in-arm in Brentwood, California, but a source told PEOPLE at the time that the pair were merely having “some fun” at the expense of photographers.
And in November, the duo stepped out together in West Hollywood on Monday for a night on the town just a day after they were spotted together at a Los Angeles Lakers game.
Although their romantic status remains uncertain, in October Erin had nothing but kind words to say about McPhee. “She’s amazing. I really like her. She’s awesome,” Erin, 35, exclusively told PEOPLE. “My dad is kind of a hopeless romantic, and Katharine’s awesome. We really, really like her, and we’ve known her for a really long time. And if he’s happy, we’re happy.”
And despite the fact that he’s been through four divorces — most recently finalizing his separation from Yolanda Hadid earlier this month — the legendary producer is open to walking down the aisle again.
“It’s quite obvious by my track record that I love being married, so I wouldn’t say no to being married again,” Foster told PEOPLE exclusively. “I like the concept, I’m just not that good at it.”