Heat the oil in a large soup pot over medium heat. Add the onion and cook until translucent and starting to brown, about 3 minutes. Add the celery, bell pepper, potato, and garlic and cook for about 2 minutes more. Add the salt and 3 cups of the corn kernels and stir. Add the broth and let it all simmer for about 10 minutes, until the potato is tender.

Turn off the heat. Using an immersion blender or a regular blender, purée the soup until you it is nice and creamy. If you used a regular blender, put the soup back in the pot and reheat slowly. Add the rest of the corn and the lemon juice. Bring back to a slow simmer. Turn off the heat, add the torn basil, and taste. Adjust the seasonings. Serve with fresh basil. Bon appétit!