Edamame is just a fancy word for heart-healthy soybeans--used here in place of traditional lima beans. Look for them in the frozen vegetable case.
Sauté onion in hot oil in a large skillet over medium heat 3 minutes or until tender. Add bell peppers and corn, and cook 5 more minutes or until tender.
Stir in chicken broth, and bring to a boil over medium-high heat; reduce heat to low. Stir in edamame; cook 3 minutes. Stir in butter until melted. Remove from heat, and stir in mint and salt and pepper to taste. Serve immediately.
Not the absolute best I've ever had, but it was very satisfying, and it's a great way to get some protein-rich soybeans into your dinner! Will make again.