I have not personally substituted Jiffy corn muffin mix in this recipe yet, but it's on my radar to try in the near future. That doesn’t mean you can't try! After all, recipes are meant to be experimented with. If I was going to substitute, I would eliminate the cornmeal, baking soda, and flour and substitute for 1 box of Jiffy. I make no guarantees it will "work,” but in theory, it should be fine and provide a sweet taste.