Chop egg whites; add to potatoes with celery and green onion. In a small bowl, combine mayonnaise, sour cream, horseradish, ...

The sour cream adds a distinct tanginess and creaminess that sets it apart from other noodle casseroles. Often, cottage cheese (or ricotta) is also incorporated into the cheese mixture.

even more so than sour cream, I think that flavor masked the taste of the butter, salt, and eggs and resulted in an overall blandness. The dish also was slightly watery and left a small pool of ...