Complex sentence: The show was a Sesame Street-esque live action puppet show which aired on Cartoon Network and was produced by Sesame Workshop about Chelli, a puppet dog voiced by Kevin Clash (who is best known as Elmo on Sesame Street), and his best friend Bag.
Split into simpler sentences: The show was a live action puppet show which aired on Cartoon Network and was produced by Sesame Workshop. The principle Muppet character was Chelli, a puppet dog voiced by Kevin Clash (who is best known as Elmo on Sesame Street), and his best friend Bag.