City Lights - The Moving Flower
During the poignant ending of City Lights, when the once blind flower girl meets her unexpected benefactor, Chaplin is holding a flower.
During the scene, which is continuous and in real time, when the camera is on Chaplin's face, he is chewing on the flower petals.
However when the camera cuts to the flower girl, Chaplin's flower is off to side and down a bit from his face.
This recurs about 2-3 times.