My sister-in-law has been making this for several years now and it is so popular with her nieces that they get their own casserole to take home with them after dinner. She started sending home casseroles with the girls because there is never any leftovers!
Boil the potatoes with the skins on. Let cool, then peel and shred into a large bowl.
Blend together the sour cream, cream of chicken soup and butter in a small sauce pan over medium heat, stirring frequently.
Chop the green onions. Shred the cheddar cheese. Cook and crumble the bacon.
Place 1/3 of the potatoes in a 9X13 dish, then pour 1/3 of sauce over potatoes. Sprinkle with onions, 1/3 of cheese, then 1/3 of bacon. Repeat layers two more times. Sprinkle top with bread crumbs and any remaining bacon crumbles.