Dead pan

This master comedian of dead pan delivery, perfect timing and the supreme usage of the pause to milk the audience laughter, actually started in vaudeville as a “class act” with his playing the violin and a partner as a pianist.

Source: wiktionary

He was happy to acknowledge the outstanding ovation with his dead pan face and speak in his unique French Canadian accent.

Source: wiktionary

I can't imagine that Jesus could have inspired and led crowds of people with a serious dead pan expression; it is more likely he had a sense of humor, and endless love for people.

Source: wiktionary

Here a young man, perhaps sixteen, is sitting with his back to the rock among some ferns playing a guitar, dead pan.

Source: wiktionary