1. 1. Preheat the oven to 375°F (190°C).

2. 2. Peel and thinly slice the Idaho potatoes.

3. 3. In a skillet, heat the extra-virgin olive oil over medium heat. Add the ground beef and cook until browned. Season with black pepper, garlic salt, and fine salt to taste.

4. 4. In a separate skillet, sear the boneless beef sirloin steak until browned on both sides. Slice it thinly against the grain.

5. 5. Grease a baking dish with salted butter. Layer the sliced potatoes at the bottom of the dish.

6. 6. Pour half of the condensed tomato soup over the potatoes. Add a layer of cooked ground beef on top.

7. 7. Place a layer of sliced beef sirloin steak on top of the ground beef. Sprinkle with lemon pepper and additional black pepper.

8. 8. Cover the meat with a layer of American cheese slices.

9. 9. Repeat the layers until all ingredients are used, finishing with a final layer of American cheese slices on top.

10. 10. Cover the baking dish with foil and bake for 45-50 minutes or until the potatoes are tender and the cheese is bubbly.

11. 11. Remove from the oven, let it cool slightly, then serve hot.

12. 12. Enjoy this delicious Cheesy Beef Potato Casserole!