In a large pot, heat oil over medium to medium-high heat until hot. Add onions and garlic and sprinkle with salt. Sauté, stirring as needed to prevent browning, until the onions are softened.

Add stock, cauliflower, potatoes, cayenne, cumin, oregano, and one to two teaspoons salt (less if using store-bought broth). Bring to a boil, turn heat to low, and cover. Cook for 20 minutes or until the cauliflower and potatoes are soft.

If you aren’t using any extra toppings, remove about six florets of the cauliflower and set aside to cut into small bits to garnish the soup.

Using an immersion blender, blend the soup until smooth, or transfer it in small batches to a blender or food processor to purée. Add salt and pepper to taste. Top with the chopped cauliflower florets or other topping(s) of your choice.