1. In a large saucepan oiled (olive oil), fry the carrots, celery onion for 3 minutes. Add broccoli, cook 3 minutes longer. Stir in 2 3/4 cups milk, salt, thyme, and pepper.
2. Bring to boil. Reduce heat; cover and simmer for 5 - 10 minutes or until vegetables are tender. Combine the flour and remaining milk until smooth; gradually stir into the soup. Bring to a boil; cook 2 minutes longer or until thickened.