In a large saucepan, saute the mushrooms in the safflower oil for 3 minutes. Add the green onion, garlic, and ginger, and saute an additional 2 minutes. Add the water and Swiss chard and stir well to combine. Bring the mixture to a boil, and allow to boil for 3 minutes. In a small bowl, stir together the miso and a little of the cooking liquid from the saucepan. Add the miso mixture and toasted sesame oil to the pot, stir well to combine, and remove the soup from the heat. Sprinkle sesame seeds over individual servings.
Yield: 1 1/2 Quarts