Cook the following until tender

• 1/2 cup grated carrots
• 1/2 cup finely cut celery
• 4 Tablespoon grated onion
• 1 cup water

• 1/4 cup butter
• 6 Tablespoons flour
• 2 cups chicken broth
• 2 cups milk
• 1/2 pound sharp cheddar cheese
• salt and white pepper to taste