Jason Sudeikis Only the Good Sing Billy Joel Covers

12/29/2013 12:26 PM PST

It was nine o'clock on a Saturday ... an unsuspecting Kansas City bar crowd gathered round to watch a popular cover band  ... but they got a big bonus ... Jason Sudeikis.

The SNL star and his fiancee Olivia Wilde hit up Kanza Hall ... and Jason joined the band Summer Breeze for some classic hits -- including Billy Joel's "Just the Way You Are."

Jason's got a pretty decent set of pipes.