Step 1: Cook the pasta

• Cook the pasta according to package instructions until al dente. Drain and toss with butter, beaten eggs, and grated Parmesan. Set aside.

Step 2: Make the meat sauce

• Heat olive oil in a large skillet over medium heat. Add the chopped onion and garlic, sautéing until softened.
• Add the ground lamb or beef, cooking until browned and fully cooked.
• Stir in the tomato paste and cook for 1–2 minutes. Add the crushed tomatoes, red wine, cinnamon, nutmeg, salt, and pepper. Simmer for 20 minutes, allowing the flavors to meld.

Step 3: Prepare the béchamel sauce

• In a medium saucepan, melt butter over medium heat. Whisk in the flour and cook for 1–2 minutes, stirring constantly.
• Gradually add the warmed milk, whisking until the sauce thickens and becomes smooth.
• Remove from heat and whisk in egg yolks, nutmeg, Parmesan cheese, salt, and pepper. Set aside.

Step 4: Assemble the pastitsio

• Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking dish.
• Spread half of the cooked pasta evenly in the dish. Top with the meat sauce, spreading it evenly.
• Add the remaining pasta on top of the meat sauce.
• Pour the béchamel sauce over the top layer, spreading it evenly to cover.

Step 5: Bake the pastitsio

• Place the dish in the oven and bake for 45 minutes, or until the top is golden brown and bubbly.

Step 6: Rest and serve

• Let the pastitsio cool for 10 minutes before slicing. Serve warm with a side salad or crusty bread.