In a cast iron skillet, add red shishito peppers, oil, onion, and garlic.

Cook until the peppers are blistered. Stir frequently. It is okay that the onions and garlic get caramelized.

Remove peppers and cut off the stems.

Add all ingredients into a blender.

Puree until smooth.

Pour the soup mixture into a pot. Cover and bring to a boil.

Boil for 5 minutes, then reduce the heat and simmer an additional 10 minutes.

Serve hot with sour cream, cilantro and even jalapeño slices.