In large stockpot, heat olive oil over medium heat. Add onion, carrot, and celery, stirring occasionally for 5 to 7 minutes until softened. Add garlic and cook an additional 3 minutes. Add tomatoes, sun-dried tomatoes, vegetable broth, bay leaves, and pepper. Simmer until vegetables are tender, about 20 minutes. Add basil and stir. Ladle into individual bowls, top with croutons, and serve.