In 5- to 5-1/2-quart slow cooker, place coleslaw mix, onion, carrots, yellow squash, zucchini, garlic, diced tomatoes, chicken broth, kidney beans, water, prosciutto, Italian seasoning, salt, black pepper and red-pepper flakes; stir to combine.
Cover slow cooker; cook on high heat for 4-1/2 hours.
Stir ditalini into mixture in slow cooker. Cover; cook 30 minutes.
To serve, spoon into bowls. Sprinkle with Parmesan, if desired. Makes 8 servings.