1. Cook pasta according to package directions, omitting salt and fat; drain.
2. Cook bacon in a large nonstick skillet over medium heat until crisp. Remove bacon from pan, reserving drippings in pan. Finely chop bacon; set aside. Increase heat to medium-high. Add chicken to drippings in pan; sauté 6 minutes or until done.
3. Heat oil in a large saucepan over medium heat; sprinkle flour evenly into pan. Cook 2 minutes, stirring constantly with a whisk. Combine milk and soup, stirring with a whisk; gradually add milk mixture to saucepan, stirring with a whisk. Bring to a boil; cook 2 minutes or until thick. Remove from heat; let stand 4 minutes or until sauce cools to 155°. Add Italian cheese blend, onion powder, garlic powder, dill, and salt, stirring until cheese melts. Stir in pasta and chicken.
4. Preheat broiler.
5. Spoon mixture into an 8-inch square baking dish coated with cooking spray. Sprinkle evenly with reserved bacon and colby-Jack cheese. Broil 3 minutes or until cheese melts.