Preheat your oven to 375°F (190°C) and grease a 9×13-inch baking dish with olive oil.

Heat 2 tablespoons of olive oil in a large skillet over medium heat. Sauté the chopped onion for about 3–4 minutes until translucent, then add minced garlic and sauté for an additional 30 seconds.

Add the lean ground beef to the skillet, breaking it into crumbles. Cook for 6–8 minutes until browned, then drain excess fat and season with paprika, oregano, salt, and pepper.

In a medium bowl, combine 1 cup of Greek yogurt, ½ cup of sour cream, and 1 tablespoon of cornstarch. Whisk until smooth.

Layer half of sliced potatoes in the prepared baking dish, then add half of the beef mixture, half of the creamy yogurt mixture, and half of the cheese. Repeat these layers.

Pour the beef broth around the edges of the casserole, ensuring it seeps into the layers.

Cover the dish tightly with aluminum foil and bake for 45 minutes.

Remove foil and bake for an additional 15–20 minutes until potatoes are fork-tender and cheese is bubbling.

Let the casserole rest for about 10 minutes before serving. Garnish with parsley.