Making Hamburger Potato Casserole is enjoyable, and following these simple steps will ensure success:

1. Preheat the Oven: Preheat your oven to 375°F (190°C).
2. Cook the Ground Beef: In a large skillet, cook the ground beef over medium heat until browned, about 5-7 minutes. Drain excess grease.
3. Add Onions: Incorporate the chopped onion into the skillet and cook until softened, about 3-4 minutes.
4. Combine Ingredients: In a large bowl, mix together the cream of mushroom soup, milk, garlic powder, salt, pepper, and paprika.
5. Layer the Casserole: In a greased 9×13-inch baking dish, layer half of the sliced potatoes. Spread the ground beef mixture evenly over the potatoes.
6. Add Vegetables: If using, sprinkle the frozen mixed vegetables over the ground beef layer.
7. Pour the Soup Mixture: Pour the soup and milk mixture evenly over the top.
8. Add the Remaining Potatoes: Place the remaining slices of potatoes on top of the casserole.
9. Cover and Bake: Cover the dish with aluminum foil and bake for 30 minutes.
10. Add Cheese and Bake Again: After 30 minutes, remove the foil, sprinkle the shredded cheese on top, and return the dish to the oven for an additional 15-20 minutes until potatoes are tender and cheese is bubbly and golden.
11. Serve: Once cooked, allow the casserole to cool for a few minutes before serving.

Using these straightforward steps, you will have a delicious Hamburger Potato Casserole ready that everyone will rave about.