The Gummy Cake is a Crock Pot dish introduced in the Hamlet DLC. It requires at least 1 raw or cooked Gummy Slug and at least 1 Sweetener, even if the value of this sweetener cannot excess 2. At the exception of another slug, fillers can’t be meats. It is possible for the filler to be twigs.
Gummy Cake is one of the best hunger-restoring food items in the game, tied with the Meaty Stew. It restores 150 Hunger when eaten (which corresponds to the whole Hunger bar of all the characters, except Wolfgang, Webber, upgraded WX-78, or Warly), but at the cost of 3 Health and 5 Sanity.