Sauté Veggies: In a large soup pot over medium heat, warm olive oil. Add onion, garlic, poblano, potatoes, and corn. Sauté for 6-8 minutes until potatoes begin to soften.
Add Liquids: Stir in coconut milk, vegetable broth, and sour cream (if using). Scrape up any bits stuck to the pot. Season with salt and pepper.
Simmer: Reduce heat to low and let simmer uncovered for 10-15 minutes, or until potatoes are fork-tender.
Blend for Creaminess: Blend half the soup (carefully!) and return it to the pot. Stir to combine. Adjust seasoning as needed.
Serve & Garnish: Top with cilantro, scallions, and an optional swirl of sour cream or goat cheese. Serve with bread or crackers.