LOVE LOVE LOVE edamame!
There are a lot of things you can do to season they even while they are in the pod.
-Minced fresh, raw garlic and a few drops of chili oil.
-Minced sauteed garlic with a bit of butter.
-Soy sauce and butter, melted (salty though!)
Those above are more traditional but if you think popcorn seasoning, you can sprinkle just about any seasoning you like, including parmesan cheese and chili powder.
