Saute onions in olive oil until translucent. Add garlic and cubed zucchini stirring until zucchini begins to brown. Add 6 cups of water, and stir because this is the last stir for a while. Add the soy flour and nutritional yeast but do not stir. Cover and cook until the zucchini is soft. Using an immersion blender, blend until smooth. Blend 2 T cornstarch with water then stir into soup over low heat. When the soup reaches the desired consistency, add the dill and miso paste (can be diluted with water or soup to dissolve easier) and stir. Serve.