This summertime favorite is sweet and satisfying, bursting with pure, clear corn flavor right from your own corn cob broth.
- 12 ears sweet corn, shucked
- 10 cups water
- 1 teaspoon kosher salt
- 1 very large Vidalia or Walla Walla onion
- 2 stalks celery, trimmed
- 2 large russet potatoes (about ½ pound)
- 1 tablespoon olive oil
- 2 teaspoons agave nectar
- 2 teaspoons salt
- 1 teaspoon freshly ground black pepper
- 2 teaspoons chopped fresh thyme leaves
- Corn kernels reserved from the stock
- Make the stock: Cut the corn kernels from the cobs (see Kitchen Tip; there should be about 5 cups of kernels). Transfer the kernels to a bowl and set aside. Place the cobs into a large stock pot. Add the water and salt and bring to a boil over high heat. Reduce the heat to medium and simmer uncovered for 2 hours.
- Cut the onion into ½-inch dice (you should have about 2 cups). Cut the celery into ½-inch dice (you should have about 1 cup). Peel and cut the potatoes into 1-inch dice.
- Pour the oil into a Dutch oven or wide, deep pot set over high heat, and heat for 2 to 3 minutes, until the oil begins to shimmer. Add the onions and stir to coat. Reduce the heat to medium-low and stir in the agave, salt, and pepper. Cook for 10 to 15 minutes, stirring occasionally, until the onions have caramelized evenly.
- Add the celery and thyme and cook for 3 to 4 minutes, until the celery is soft.
- When the stock is done, use tongs to remove and discard the cobs.
- Add the potatoes, reserved corn kernels, and corn stock to the pot with the onions and celery. Increase the heat to high and bring to a boil. Reduce the heat to medium-low, cover, and simmer for 15 to 20 minutes, until the potatoes are soft and easily pierced with a knife.
- Carefully transfer half of the soup to a food processor or blender and pulse or blend until smooth and creamy. Return the soup to the pot and heat through (alternatively, partially blend the soup in the pot with an immersion blender; be sure to keep a partially chunky consistency). Ladle into bowls and serve warm.
- Choose the freshest corn, still in its husk. To store at home, shuck it and snap off its exposed bottom. Store in the refrigerator wrapped tightly with plastic or in a resealable bag.
- To cut the kernels off a fresh ear of corn, shuck it well and place it on a work surface. Cut it in half crosswise. Stand it on the work surface, cut side down, and with a sharp knife, cut downward to remove the kernels.