Whisk together the ginger, garlic, miso, soy sauce, mirin, sesame oil and water and set aside.In a large pan, sauté the diced onion and pepper with a pinch of salt for 4 minutes on medium heat, until tender and the onions are translucent.Add the thawed corn and edamame and sauté for another 3 to 4 minutes, until they are cooked through.Add the sauce and sliced scallions to the pan and sauté for 1 to 2 minutes more. Remove from the heat and serve topped with sesame seeds.