It’s The Elder Scrolls Online 7 year anniversary! To celebrate they will be holding the Jubilee Event from April 1 – 13th. Here is the link for more information: https://www.elderscrollsonline.com/en-us/news/post/59783?linkId=114525492
Remember once you eat a slice of your cake, you will receive a 100% XP boost for 2 hours. Great way to level a new or existing character.