- 2 tablespoon unsalted butter
- 8 ears fresh corn (kernels removed)
- 5 clove garlic (peeled and minced)
- 3 stalks celery (small diced)
- 1 teaspoon ground cumin
- ½ teaspoon ground coriander
- kosher salt (as needed)
- 2 cup small diced peeled pumpkin (or other orange-fleshed winter squash)
- 2 bay leaves
- 2 teaspoon fresh lime zest
- 1 teaspoon chipotle chile powder (or to taste)
- 4 cup water (or more as needed)
- 8 ounce sour cream (or more as needed, divided)
- lime wedges (as needed)
- 6–8 crisp tostada rounds (or tortilla chips)
- crumbled cotija cheese (as needed)
- fresh cilantro (as needed)
Melt the butter in a large non-stick skillet (at least 12 inches) over medium-high heat, add the corn kernels, toss and let it sit in as close to a single layer as possible until lightly charred, about 6 minutes, mix it up and let it char again about 6 minutes. Turn off the heat and set aside. If you do not have a large enough skillet work in batches.
Heat the oil in a medium soup pot, add onion, garlic, celery, ground cumin, ground coriander, and a little salt, and sauté stirring often on low heat for 12 minutes, to soften the vegetables.
Add the pumpkin, bay leaves, lime zest, chipotle chile powder, and water. Bring to a boil and simmer for 15 minutes, or until the pumpkin is soft. Add the charred corn and cook for five minutes.
Use a slotted spoon to lift out about half of the vegetables, and remove and discard the bay leaves. Blitz the remaining soup until smooth, then return the vegetables to the pot and bring to a light simmer. Add a little more water if you find it too thick. Stir in half the sour cream and taste for seasoning.
Divide the soup into six bowls, squeeze the juice of half a lime into each portion, lay a crisp tostada round on top, and drop about a tablespoonful of sour cream in the middle. Garnish with plenty of crumbled cotija cheese and cilantro. Serve with additional lime wedges on the side.