In a large pot, heat the oil on medium high heat. Add the onions and saute until translucent. Add the garlic and saute for 30 seconds more. Then add the potatoes, carrots, corn, salt, thyme, garlic powder, onion powder, rosemary, and black pepper. Saute for another 2-3 minutes.
Pour in vegetable broth and bring to a boil. Lower heat and let it simmer for 15 minutes or until vegetables are soft and fork tender.
Once vegetables are softened, drain the cashews and add it to your blender. Add about half of your soup (or however much you want depending how chunky or smooth you like your soup) to the blender and optional nutritional yeast and blend on high for 30-45 seconds, or until nice and creamy.
Pour soup from the blender back into the pot and stir until everything is combined. Taste and adjust seasonings, like salt and pepper if needed. Enjoy!