The essence of sweet, just-picked summer corn. Serve it hot or cold. Prep and Cook Time: about 1 hour, plus at least 2 hours to chill if served cold. Notes: Trombetta zucchini is pale green and curvaceous. Queso fresco is a mild, Mexican-style cheese.
3 large poblano chiles
10 ears freshly picked corn
2 tablespoons olive oil
1 large yellow onion, chopped
1 to 2 serrano chiles, finely chopped
About 2 tsp. sea salt
4 large garlic cloves, minced
1 Trombetta zucchini (see Notes; 7-in. piece) or 1 medium regular zucchini, seeded and cut into 1/4-in. dice (about 1 1/2 cups)
Turn on broiler. Put poblanos on a foil-lined rimmed baking sheet and roast 4 in. from heat, turning once, until blackened, 10 to 15 minutes total. Put poblanos in a bowl, cover, and let sit 30 minutes to loosen skins; then peel, stem, and seed. Cut poblanos into 1/2-in. dice and set aside.
Meanwhile, slice corn kernels from cobs. Heat olive oil in a large, wide pot over medium heat and add onion, serranos, and 2 tsp. salt. Cook, stirring occasionally, until softened, 5 minutes. Stir in garlic and corn kernels and cook 3 minutes more.
Pour just enough water into pot to cover corn. Bring to a simmer, covered, and simmer 15 minutes.
Put diced zucchini in a small saucepan with just enough salted water to cover. Bring to a simmer and cook until tender-crisp, about 2 minutes. Drain.
In batches, whirl corn soup in a blender until very smooth. Strain through a fine-mesh colander into a bowl, mashing to press out liquid. (If too thick, add some water.) Season with salt. To serve the soup hot, return to pot and reheat gently (do not boil); to serve cold, chill at least 2 hours.
Divide among 8 bowls. Top each bowl with 2 tbsp. diced poblanos, 2 tbsp. diced zucchini, and 2 zucchini blossom halves. Sprinkle each with 1 tbsp. cheese and serve the extra on the side.