Heat olive oil in a large nonstick skillet coated with cooking spray over medium-high heat. Add mushrooms, onion, and bell pepper
; sauté 4 minutes or until tender. Add spinach, oregano, and black pepper; sauté 3 minutes or just until spinach wilts.
Place cottage cheese in a food processor; process until very smooth. Combine spinach mixture, cottage cheese, pasta, chicken, 3/4 cup cheddar cheese, 1/4 cup Parmesan cheese, milk, and soup in a large bowl.