In a large pot, add the olive oil, chopped broccoli, chopped carrots, and peeled and cubed potato. Season with a little salt and pepper and cook over medium to high heat. After a minute add the chopped shallot and allow to cook another 1-2 minutes. Then add the minced garlic and cashews and cook another minute.
Pour in the vegetable stock, reduce the heat to low, and over the pot. Allow to simmer for 18-22 minutes until the potatoes are soft enough that you can easily cut them with a wood spoon (or whatever you stir your soup with).
Add the nutritional yeast and blend the soup well. You can do this either in a blender or with an immersion blender. Then stir in the milk, add the cayenne, and season with salt and pepper to taste.