Boil the bucatini pasta in salted water until al dente. Drain well. Drizzle with a few drops of extra virgin olive oil, gently mix to prevent sticking, and set aside.

Heat 7 tablespoons of extra virgin olive oil in a large pan over medium-high heat. Add the ground beef and cook until browned. Pour in the white wine, allowing it to evaporate. Stir in the blended onions and garlic, cooking for 2 minutes. Add the blended tomatoes, tomato juice, bay leaf, cinnamon stick, and season with salt and pepper. Reduce the heat to medium, cover with a lid, and let the sauce simmer for about 25 minutes. Remove the bay leaf and cinnamon stick before assembling the dish.

In a separate saucepan, heat the milk over medium heat. Gradually whisk in 6 tablespoons of cornstarch, then add the butter. Continue stirring until the sauce begins to thicken, making sure to stir the bottom to prevent sticking. Add nutmeg, salt, and pepper to taste, and continue stirring. Stir in half of the grated cheese until melted. Remove from heat and let the sauce cool slightly before whisking in the egg yolks.

Preheat your oven to 350°F (175°C). Grease a 33-inch baking pan (approximately 33x22 cm). Spread half of the cooked pasta evenly across the bottom of the pan. Pour the ground beef sauce over the pasta, spreading it out evenly. Add the remaining pasta on top of the sauce. Pour the béchamel sauce over the pasta, spreading it evenly to cover the top. Sprinkle the remaining grated cheese over the béchamel sauce.

Bake the Pastitsio in the preheated oven for about 1 hour, or until the top is golden and the béchamel is set. Allow the dish to cool slightly before serving.