Cut chicken into serving-size pieces. In a large shallow dish, combine the flour, salt and pepper. Add chicken, a few pieces at a time, and turn to coat.
In a large skillet, brown chicken in oil in batches. Transfer to a 5-qt. slow cooker.
Stir in the broth, tomatoes, mushrooms, onion, prosciutto, pimientos, garlic and Italian seasoning. Cover and cook on low for 4 to 4-1/2 hours or until chicken juices run clear. Serve with a slotted spoon over linguine; sprinkle with cheese.