🥔 Cheesy Beef & Potato Casserole

Preheat: Preheat the oven to 400°F (200°C). Grease a 9×13-inch (23×33 cm) baking dish.
Par-cook potatoes: Place sliced potatoes in a pot of salted water. Bring to a boil and simmer 4–6 minutes until slightly tender but not falling apart. Drain and set aside.
Cook the beef: In a large skillet, heat olive oil over medium heat. Sauté onion until translucent (3–4 min). Add garlic and cook 30 sec. Add ground beef, break up with a spoon, and cook until browned. Drain excess fat if needed.
Season: Stir in tomato sauce, paprika, oregano, salt and pepper. Simmer 4–5 minutes to let flavors meld. Remove from heat.
Layer: Spread a thin layer of the beef mixture on the bottom of the baking dish. Arrange a single layer of potato slices over it. Spoon more beef over potatoes, then another potato layer. Continue until ingredients are used (finish with beef layer).
Cheese: Sprinkle mozzarella (and cheddar if using) evenly over the top.
Bake: Cover loosely with foil and bake 25 minutes. Remove foil and bake another 12–15 minutes until cheese is golden and bubbling and potatoes are tender when pierced.
Rest & serve: Let the casserole rest 5–8 minutes. Garnish with chopped parsley, slice and serve warm.

Tips & Variations

Smoother sauce: Add 2–3 tbsp tomato paste with the sauce for a richer flavor.
Extra veg: Add a layer of sautéed mushrooms or bell peppers with the beef.
Cheesy center: Mix some ricotta or cream cheese into the beef for a creamier bite.
Make-ahead: Assemble, cover and refrigerate up to 24 hours. Add ~10 minutes to baking time if baking straight from the fridge.
Stovetop shortcut: For a faster version, cook thin potato slices in a skillet until almost tender, then finish under the broiler after layering.