01 - 
                Preheat the oven to 350 degrees F (175 degrees C). Grease a 10-inch pie plate with 1 tablespoon butter.
              
              
              
                02 - 
                Bring a large pot of lightly salted water to a boil. Cook spaghetti in boiling water, stirring occasionally, until tender yet firm to the bite, about 12 minutes. Drain and return to the pot.
              
              
              
                03 - 
                Stir Parmesan cheese, beaten eggs, and 2 tablespoons butter into hot spaghetti until well combined. Form the mixture into a crust in the prepared pie plate and set aside.
              
              
              
                04 - 
                Heat a large skillet over medium-high heat. Cook and stir beef, onion, bell pepper, and garlic in the skillet until beef is crumbly and browned, about 5 to 7 minutes. Drain off fat and stir in diced tomatoes, tomato paste, sugar, and oregano. Cook, stirring occasionally, until heated through.
              
              
              
                05 - 
                Spread cottage cheese over the spaghetti crust, then pour in the beef-tomato mixture.
              
              
              
                06 - 
                Bake in the preheated oven for 20 minutes. Sprinkle mozzarella cheese over the top of the pie and continue baking until the cheese is melted, about 5 minutes more.