In a large saucepan, sauté onions, carrots, and celery in two tablespoons butter, until tender.

Add two cans of corn, parve chicken broth, and optional rosemary. Bring to a boil.

Reduce heat; simmer, uncovered, for 30 minutes, stirring occasionally.

Cool; process in batches in a blender or food processor until pureed. Return to the pan.

Stir in milk and remaining two cans of corn; heat well, stirring occasionally. Season with salt and pepper.