Preheat the oven to 350°F (175°C).
In a large skillet, brown the ground beef over medium heat.
Add the chopped onion and cook until softened.
In a greased baking dish, layer the sliced potatoes, followed by the cooked beef and onion mixture.
Add the drained green beans on top.
Spread the cream of mushroom soup over the top and season with salt and pepper.
Cover with aluminum foil and bake for 1 hour.
Remove the foil, sprinkle cheddar cheese on top, and bake for an additional 10-15 minutes until the cheese is melted and bubbly.