Hough and Hudson, 35, reportedly arrived at the restaurant at 11PM and "were totally kissing," a source told Us. "So scandalous!"
The couple's date and PDA occurred just days before the announcement Hudson and her fiance Matt Bellamy, the frontman of Muse, had decided to split after about four years together.
However, Hudson and Bellamy -- who are parents to three-year-old Bingham Hawn Bellamy -- were apparently already over by that point.
"Kate and Matt have been separated for some time now," a representative for Bellamy, 36, told the magazine on Tuesday. "Despite this, they remain very close friends and committed co-parents."
According to a Hudson friend, the How to Lose a Guy in 10 Days star also feels the breakup is amicable.
"She says that Matt's a really great guy, but they're no longer together," the friend reportedly said. "[It] wasn't anything big and emotional."
Hudson began dating Bellamy in 2010 and the couple got engaged in April 2011. In addition to their son Bingham, Hudson also has a 10-year-old son Ryder from her previous marriage to Chris Robinson, which ended in November 2006.