Peel and cube the potatoes, then place them in a large pot of salted water. Bring to a boil and cook for 15–20 minutes until fork-tender. Drain and mash with milk, butter, and a pinch of salt and pepper until creamy.

In a large skillet, heat olive oil over medium heat. Add onion and garlic, sauté for 3–4 minutes until translucent. Add ground beef, cooking for 6–8 minutes until browned. Drain excess fat.

Stir in tomato paste, dried Italian seasoning, and desired spices. Pour in broth and frozen mixed vegetables, simmer for 5–7 minutes until thickened. Season with salt and pepper.

Preheat the oven to 375°F (190°C). In a greased baking dish, spread half of the mashed potatoes. Layer meat mixture over potatoes, sprinkle with cheese. Top with remaining mashed potatoes and another layer of cheese.

Bake uncovered for 25–30 minutes until cheese is melted and bubbly, with a golden brown top.

Cool for 5–10 minutes before garnishing with parsley or green onions before serving.