Carmichael wrote the melody, based on a Bix Beiderbecke cornet improvisation, as "Bix Licks", for a project to turn the novel Young Man With a Horn into a Broadway musical. After that project failed, Carmichael brought in Johnny Mercer to write lyrics for the song.
Carmichael penned the tune, inspired by Bix Beiderbecke's cornet solo, titled "Bix Licks", as part of an effort to transform Young Man With a Horn into a stage musical. After that initiative fell through, Carmichael collaborated with Johnny Mercer to craft lyrics for the song.