Jelly Candy is an item found in Paper Mario: The Thousand-Year Door by mixing a Jammin' Jelly and Cake Mix. It revives sixty-four FP. It is essentially the same as a Jelly Pop from the first Paper Mario.
This is the top FP healing item in the game. Mario's FP will have to be level uped above average (65+) for this not to be a full heal.