In a small saucepan over high heat, combine the quinoa and water and bring it to a boil. Cover, then reduce the heat to low, allowing the quinoa to cook for 15 minutes, until all of the water is absorbed. Fluff the cooked quinoa with a fork, and set aside.
Melt the coconut oil in a large skillet over medium heat, and sauté the chopped onion and pepper for 5 minutes. Whisk together the sauce ingredients, then add the broccoli, zucchini, and sauce to the skillet, and stir well to coat. Cover the skillet with a lid, and allow the veggies to steam in the sauce until tender, about 8 to 10 minutes.
Add in the cooked quinoa, and stir well to make sure the sauce is evenly distributed. Season with salt, if desired (additional salt isn't necessary when using tamari or soy sauce), and serve immediately, with a garnish of sliced green onions, if desired.