Preheat your oven to 350°F (175°C).

Peel (if desired) and thinly slice the potatoes. Set aside.

In a skillet over medium heat, cook the ground beef and onion until the meat is browned and the onion is soft. Drain any excess fat.

Season with salt and pepper to taste.

In a bowl, mix together the condensed soup, milk, and sour cream until smooth.

In a greased 9x13 inch baking dish, layer half of the sliced potatoes.

Spread half of the cooked ground beef over the potatoes.

Pour half of the creamy sauce over the beef and potatoes.

Repeat the layers with the remaining potatoes, beef, and sauce.

Sprinkle the top with shredded cheddar cheese and a dash of paprika or dried herbs if using.

Cover the dish with aluminum foil and bake in the preheated oven for 1 hour.

Remove the foil and bake for an additional 20-30 minutes, or until the potatoes are tender and the top is golden and bubbly.

Let the casserole cool for a few minutes before serving to allow it to set for easier slicing.