Kaley Cuoco stumped when asked about ex-boyfriend Henry Cavill

US actress Kaley Cuoco was not keen to talk about her brief fling with Henry Cavill when asked a very awkward question.

Kaley Cuoco was utterly stumped when asked a question about ex-boyfriend, Henry Cavill.

The Big Bang Theory actress, 35, reportedly dated the Man of Steel actor for a few weeks in July 2013 when they shared a handful of dates together and fast became hot tabloid fodder.

Kaley Cuoco and Henry Cavill had a string of highly-publicised dates. Picture: Backgrid AKM-GSI

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But the flame burnt out pretty fast, with the couple reportedly splitting after two weeks.

Appearing on Watch What Happens Live, host Andy Cohen asked the star, “Is the Man of Steel really made of steel?”

A clearly caught offguard Cuoco said, “Oh my god”, before breaking out in laughter.

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Kaley Cuoco on Watch What Happens Live with Andy Cohen.

“I don’t know. I never say ‘I don’t know’, I always have an answer, but I don’t know.”

Cavill, 37, shot to notoriety as Superman in the 2013 movie Man of Steel.

At the time, Cuoco wrote on Twitter: “Everyone, go see Man of Steel. It’s fantastic in every single way.”

Cuoco, who is currently starring on the gripping new series The Flight Attendant, which is streaming on Binge, has since moved on with her now husband, equestrian Karl Cook.

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Kaley Cuoco and Karl Cook. Picture: Frazer Harrison/Getty Images/AFP

The couple went public with their relationship in March 2016 and were married in 2018.

Cuoco gushed about her husband in a 2017 interview with Us Weekly, saying: “I couldn’t be happier. I feel very, very lucky that I found someone like him.

“We have been each other’s true other half since day one and we can’t wait to spend forever together.”