In a large saucepan or small stockpot, cook pasta according to package directions.
Meanwhile, in a blender or food processor, combine cottage cheese, sour cream, milk, and seasoning mix and pulse to puree.
Transfer to a small saucepan and gently warm over medium-low heat.
Drain pasta and return to saucepan.
Stir in cottage mixture, chicken, shredded cheese, tomatoes, and bacon, if using.