Heat a large pot over medium heat. Add the sliced mushrooms, and cook, stirring frequently, until they start to release their oils (about 5-8 minutes). Now add the onion and sauté for about 5 minutes, until translucent. Stir in the garlic and cook for 1 more minute, being careful not to burn it.
To the pot, add the carrots, celery, green beans, corn, broccoli, cauliflower, potatoes, broth, thyme and oregano. Stir everything together and turn the heat to high. Bring the soup to a boil, them reduce the heat and simmer for about 15 minutes, or until the potatoes are fork-tender.
To a high-powered blender like a Vitamix, add the cashews and 2 cups of the soup. Blend until smooth and creamy, then add back to the pot and stir.
Add salt and ground pepper to taste. Serve warm with crusty bread and enjoy!