Preheat your oven to 350°F (175°C). Lightly grease a 9x13 inch baking dish.
Brown the Pork Chops:
Season the pork chops with salt and pepper. Heat olive oil in a skillet over medium-high heat. Add the pork chops and sear on both sides until golden brown, about 3-4 minutes per side. Remove from the skillet and set aside.
Layer the Potatoes:
In the prepared baking dish, layer the thinly sliced potatoes and onions (if using). Season with salt and pepper between the layers.
Mix the Sauce:
In a bowl, combine the cream of mushroom soup, milk, sour cream, garlic powder, and paprika. Mix well until smooth.
Assemble the Casserole:
Pour half of the sauce mixture over the layered potatoes. Place the browned pork chops on top of the potatoes. Cover the pork chops with the remaining sauce. Sprinkle shredded cheddar cheese evenly over the top.
Bake:
Cover the baking dish with aluminum foil and bake in the preheated oven for about 1 hour. After 1 hour, remove the foil and bake for an additional 15-20 minutes, or until the potatoes are tender and the cheese is bubbly and golden.
Serve:
Let the casserole stand for a few minutes before serving. This allows the sauce to thicken slightly.