In a large pot, bring water to a boil and cook the spaghetti according to package instructions. Once cooked, drain the spaghetti and allow it to cool. In a mixing bowl, combine the cooled spaghetti with the slightly beaten eggs and 1/2 cup of Parmesan cheese. Mix well until the spaghetti is evenly coated.
Preheat your oven to 350°F (175°C). Grease your pie dish or springform pan with a bit of oil or cooking spray. Carefully press the spaghetti mixture into the bottom and up the sides of the dish to form a crust. Make sure it is evenly spread and well-packed.
In another bowl, combine the cooked ground beef, sour cream, and half of the shredded mozzarella cheese. Mix until well blended.
Spread the meatless spaghetti sauce or marinara evenly over the spaghetti crust. Next, spoon the sour cream and beef mixture over the sauce, spreading it out evenly. Finally, top with the remaining mozzarella cheese.
Place the pie in the preheated oven and bake for about 30-35 minutes, or until the cheese is bubbly and golden brown. Once done, remove from the oven and let it cool for a few minutes before slicing.
