Willis kept a straight face as he walked on to David Letterman's US TV talk show with the ridiculous looking hairpiece on his head which he joked was 'slightly thinning'.
'This is all natural, it's a meat hairpiece,' he told Letterman.
'Inspired by, who's that crazy lady? Lady Gaga! Huge fan of Gaga,' he said, referring to her recent trend of wearing raw meat outfits.
'It's 100 percent ground beef sirloin, top shelf, organic.'
He then asked if Letterman was hungry and put salt and pepper on his head. Amazingly, the TV host then took a fork-full and actually started chewing.
'My man!' an amazed Willis said. 'Unbelievable ladies and gentlemen' before Letterman went offstage to spit it out.