In a large, heavy saucepan, heat olive oil over medium heat. Sauté’ celery, carrots, garlic and onions in oil about a minute. Add water and let vegetables steam another minute. Stir in chicken broth & tomatoes and bring to a boil.
Reduce heat and simmer 3 to 4 minutes or until vegetables are tender. Add chicken tenders. Stir in cannelloni beans and their liquid, return to simmer and cook, stirring once, another 7 minutes. Stir in ditalini, return to a simmer and cook an additional 3 minutes. Serve hot garnished with Parmigiano cheese.