Prepare pasta according to instructions on package.
In a large pan, heat 1 tablespoon of olive oil at medium heat. Add onion and garlic and sauté (stirring occasionally) until lightly browned.
Add sweet potato, carrots, edamame and tamari. Add 2-3 tablespoons of water to the pan. Cover and let water boil, stirring every few minutes. Keep an eye on the pan and add more water as it evaporates. There should be a light layer of water to help cook the vegetables.
After 15 minutes, check to see if the sweet potatoes are tender. They may need another 5-7 minutes to cook. When they feel thoroughly cooked, mix spinach in and cover for 2 minutes. Uncover and allow any remaining water to evaporate. Stir in pasta, nutritional yeast and the remaining two tablespoons of olive oil. Season with salt and pepper and enjoy right away!