- 6 large ears fresh corn, husked
- 1 tablespoon vegetable oil
- 1/2 cup chopped shallots (about 3 large)
- 2 tablespoons coarsely grated peeled fresh ginger
- 2 garlic cloves, minced
- 6 cups low-salt chicken broth
- 1 cup buttermilk
- Additional buttermilk
- Chopped fresh chives
- Cut corn kernels off cobs; transfer kernels to large bowl. Scrape cobs over bowl with knife to remove any remaining bits of corn and milky liquid. Break cobs in half crosswise and reserve.
- Heat oil in heavy large saucepan over medium-high heat. Add shallots, ginger, and garlic; sauté until shallots begin to soften, about 2 minutes. Add corn and any accumulated liquid in bowl. Cook until heated through, stirring occasionally, about 3 minutes. Add cobs and broth. Bring soup to boil; reduce heat to low, cover pan, and simmer until corn is very tender, about 30 minutes. Discard cobs.
- Working in batches, puree soup in blender. Transfer to large bowl. Stir 1 cup buttermilk into soup. Cover and refrigerate until chilled, at least 3 hours. (Can be made 1 day ahead. Keep chilled.)
- Season soup to taste with salt and pepper. Divide soup among 8 bowls. Drizzle with additional buttermilk, sprinkle with chives, and serve.