Preheat the oven to 425 f. Spray a large rimmed baking sheet with spray.
spread the corn on the prepared baking sheet and roast until lightly brown, 25 minutes, stirring twice during cooking.
Meanwhile, heat the oil in a large saucepan over med heat. add onions and cook, until soften , stirring occasionally, for 5 minute. Add celery and cook until softened for 3 minutes. Stir in flour and cook for 1 minute stirring constantly,to avoid browning..(don't return brown) just trying to cook of the favor of the flour..
Gradually stir in the broth until blended. Stir in the corn, potatoes, salt and pepper; bring to a boil. Reduce the heat and simmer, string occasionally, until the potatoes are fork-tender, 15 minutes. Let cook 5 minutes. Puree 2 cups of the chowder in a blender or food processor.
Stir in the remaining cup to the puree and parsley into the chowder. divide the soup into 4 bowls and sprinkle with cheese