Known as the three sisters, this soup incorporates squash, beans and corn to create a hearty but not heavy soup that is a cousin to tortilla soup. It's rich and flavorful and loaded with texture. It comes together easily and can be doubled for a big group. It's vegan and can remain that way if you don't add any yogurt or sour cream.
Preheat oven to 400 degrees.
Prepare a baking sheet with parchment paper and set aside.
Sprinkle salt and pepper on each butternut squash half and place both cut-side down on the baking sheet. Roast squash until it's soft and tender, about 1 hour or a little longer.
Remove from the oven and turn the squash cut-side up and allow it to cool.
In a heavy soup pot, place over medium heat and add the tablespoon of olive oil. Once it's hot, add the chopped onion and saute until it begins to turn a bit golden, about 10 minutes. mix in the celery and garlic and stir well to combine.
Add 1 cup of the broth, cover and simmer 10 minutes, stirring occasionally.
Now scoop the squash from the shell and add to the pot. Also add the remaining 5 cups of broth and cumin. Stir well, cover and simmer for 20 minutes so the flavors marry.
Using either an immersion blender or a blender, puree the soup so it's all smooth. If using a blender, return the soup to the pot and, if needed, thin it out with a bit more broth.
Add black beans, corn, red pepper, cilantro, jalapeno and thyme and stir well to combine. Cover soup and simmer 10 minutes.
Taste soup and add more salt, if needed, and plenty of freshly ground black pepper.
Ladle soup into bowl,s and garnish with a dollop of yogurt or sour cream, crushed tortilla chips and cilantro.