Gravy Day is an unofficial holiday observed in Australia every December 21. It was inspired by Paul Kelly's song "How to Make Gravy," which was released in 1996 and has since become a cult classic. The song is written as a letter from a man named Joe, who is in prison and reflects on his family's Christmas gathering, highlighting the significance of making gravy as part of the holiday rituals. Since at least 2015, fans have celebrated Gravy Day by sharing memes on social media, listening to Kelly's music, and perfecting their gravy recipes in preparation for Christmas dinner. The song's lyrics include a specific gravy recipe that Kelly learned from his father-in-law, which has sparked discussions among food enthusiasts. Gravy Day has grown in popularity, emphasizing the connection between the song and Christmas traditions in Australia.