Set the broiler to high and arrange the poblano peppers on a baking sheet.

Roast, turning occasionally for even cooking, until the skins are dark and the peppers are tender.

Place peppers in a container with a lid and seal to cool. Set aside while you prepare the soup base.

Steam cauliflower florets on the stove top or in a silicone steamer case until very tender. Approximately 5 minutes in the microwave or 7-10 on the stove top.

Using a high-speed blender or food processor, puree steamed cauliflower and 1 cup broth. Drizzle in the remaining broth and continue to puree until the mixture is a smooth consistency.

Heat butter and onion over medium heat in a soup pot and cook until the onion is translucent.

Add half the cauliflower puree, sour cream, and cheese to the pot and stir until thickened. Reduce to low heat.

Remove the skin and seeds from the cooled poblano peppers and dice, reserving some garnish the finished soup.

Pour the remaining cauliflower puree and diced peppers into the soup pot. Return heat to medium and simmer for about 5 minutes.

Stir in the garlic powder, smoked paprika and cumin and remove from heat. Serve hot and top with reserved peppers and optional shredded cheese.