Ingredients

• 3 ears of corn, shucked
• 1medium onion, chopped
• 1 garlic clove, finely chopped
• 2 tablespoons unsalted butter
• 4 1/2 cups water
• sour cream; chopped chives

Instructions

1. Cut kernels from cobs with a sharp knife, then cut cobs into thirds.
2. Cook onion and garlic in butter with 1/4 teaspoon salt in a large heavy saucepan over medium heat, stirring occasionally, until onion is softened, about 5 minutes. Add corn and cobs, water, 1 teaspoon salt, and 1/2 teaspoon pepper and simmer, uncovered, 20 minutes.
3. Discard cobs, then purée corn mixture in batches in a blender until very smooth (use caution when blending hot liquids). Force soup through a fine-mesh sieve into a bowl, discarding solids.
4. Chill until cold, at least 1 hour. Thin with water if desired and season with salt.