There must be 100's of versions of this casserole, but its always a favorite. Here is mine.
1 package frozen hash browns (you can also use Potatoes O'Brien)
2 cups cheddar cheese
1 can cream of chicken soup
1/2 can water
3/4 cup sour cream
1/2 cup onions (omit of using Potatoes O'Brien)
1 stick butter (melt and save 1/4 for top)
1-2 cups cornflake crumbs
Preheat oven to 350. Place potatoes in 9x13 greased pan. In a separate bowl, mix together: cheese, soup, water, sour cream, onions and butter. Pour over potatoes. Cover with layer of cornflake crumbs. Pour remaining butter over the top and bake 350 for 1 hour.