This in one of the recipes I grew up with. I'm sure there was a time when I complained to my mother about it just like Cam complains to me...every time I make. It's also a loose recipe so feel free to play with it.
1 pound ground beef
1 can cream of mushroom soup
6 medium potatoes
1/2 medium onion
Brown the beef. Thinly slice the potatoes and onion. In a greased casserole dish, layer half the sliced potatoes, half the sliced onion, salt and pepper to taste (I also like to add a little butter maybe the equivalent of a tablespoon), repeat. Top with browned ground beef. Spoon cream of mushroom soup over top and spread in an even layer, sealing the edges. Cook uncovered for 30 to 45 minutes in a 350 degree oven. You are only cooking until the potatoes are done so the thinner you cut them the quicker it cooks. I just serve with a nice green salad (Caesar on in this picture).