There are already so many great suggestions here! The only one I will add is the sweet pretzel in Norway. I know that almost everyone loves school bread, but for me it's a miss. But that sweet pretzel...delicious! We often pick up an extra one on the way out of Epcot and eat it for breakfast the next day. It comes in two varieties -- almond and I think chocolate -- and though usually anything chocolate is my favorite, in this case I prefer the almond one.
There is so much delicious food at Epcot! Our family can easily make meals out of the snacks there...and one of our favorite memories is from our last trip, where we "challenged" ourselves to find a delicious snack at every country's pavilion! As you can imagine, that challenge was easily met.