In a large bowl, combine cooked macaroni, cheddar cheese, onion, and parsley.
In a blender or food processor, combine cottage cheese, milk, and mustard. Process until smooth. Mix
in salsa and fajita seasoning and pour over macaroni mixture. Mix thoroughly. Add salt and pepper to taste.
Coat a 2-quart casserole dish with nonstick cooking spray and place macaroni mixture into dish. Sprinkle
breadcrumbs and Parmesan cheese over casserole. Bake for 20 minutes.