I have never tasted jackfruit, but my Filipino sister-in-law cooks with it frequently, so I turned to a Filipino recipe for inspiration.
https://www.kawalingpinoy.com/maja-langka/
I found this mix sweet enough without added sweetener, but feel free to add sweetener if desired. I liked this so much, I am going to buy some jackfruit just to taste the real thing, and will be buying a big bottle of jackfruit flavoring.