Mix ¼ cup rice milk with the tapioca or corn starch and set aside.
Heat 4 tablespoons of olive oil in a large skillet over low heat. Add the onions and salt and cook until the onions are very tender but not brown, about 20 minutes. Cut the zucchini in half lengthwise, then slice about ¼ inch thick. Add the pepper, nutmeg, zucchini, sun dried tomatoes and remaining ¾ cup of rice milk to the onions, raise the heat to medium, cover the pan and cook for 10 minutes or until the zucchini is fork tender.
Remove the cover, raise the heat to high, bring the mixture to a boil and stir in the rice milk starch mixture. Cook the mixture, stirring until the mixture thickens, about 1 minute. Remove from the heat and stir in the basil.
Combine the bread crumbs with the nutritional yeast. Put the zucchini mixture into a 9 by 12 inch (or similar sized) baking dish, top with the bread crumb mixture and drizzle the top with the remaining 2 tablespoons of olive oil. Bake for 20 minutes or until bubbly and browned.