The 53-year-old 'X Factor' judge was spotted enjoying a dinner date with Gavankar, who plays vampire Luna Garza in the HBO series and looks very similar to his ex-fiancee, at Los Angeles restaurant Cecconi's on December 8, reported the New York Daily News.
Though the two have remained mum about the status of their relationship, Cowell sent a flirtatious tweet to the 32-year-old actress last month, writing, "Hello trouble."
Gavankar replied, "Who me?? Definitely me. (sic)"
Cowell then responded, "Yes you. (sic)"
Cowell, who split from make-up artist Mezhgan in February, and Gavankar have since deleted the tweets from their accounts.
Gavankar, who dated US internet entrepreneur Angelo Sotira, 31, for five years before they split in 2010, was spotted smiling in the back of Cowell's chauffeur-driven car.
