It sounds like you are referring to Hash Brown Casserole
1- 2# pkg. frozen hash brown potatoes,( not the shredded ones)
1/2 cup finely chopped onion
1 can cream of mushroom soup(undiluted)
2 cups crushed corn flakes
1-2 cups chopped cooked ham
2 cups sour cream
1 tsp. salt
1 tsp.pepper
1- 8 oz. pkg. grated sharp cheddar cheese
Pour frozen hashbrowns in a large shallow casserole dish .
Add onionss, soup, ham , cheese and sour cream. Add salt and pepper. Mix well. Top with cornflakes. Bake at 350* for about one hour, until it's hot and bubbly.
NOTE; Some people melt a stick of butter and mix in with the other ingreds.. If you would like to do that you can, I don't because I think it is already rich enough.