In a large saucepan cook carrot, celery, and onion in hot oil over medium-high heat for 3 minutes, stirring occasionally. Carefully add broth, kale, beans, and tomatoes. Bring to boiling; reduce heat. Cover and simmer for 10 minutes, stirring twice. Season to taste with salt and pepper.
Divide croutons among 4 shallow bowls. Ladle soup into bowls and, if desired, sprinkle with cheese.