1. Preheat oven to 350°F. Spray a 9x13-inch baking dish with nonstick cooking spray and set aside. Cook spaghetti in a Dutch oven as directed on package, adding 3 teaspoons of the salt to water. Once the water starts boiling, add spaghetti, breaking it in half, to pan. Cook the spaghetti just until it reaches the al dente stage; take care not to overcook to prevent mushiness. Drain spaghetti thoroughly, shaking the colander to remove excess water. Return spaghetti to cooking pan to dry a bit.

2. Whisk together the eggs and 1 cup of the Parmesan cheese in a large glass mixing bowl. Add cooked spaghetti and use tongs to toss spaghetti in egg-cheese mixture to evenly coat spaghetti strands. Place spaghetti in prepared baking pan, forming a ‘crust’ and leaving center of ‘crust’ somewhat shallow to accommodate filling. Place in oven and bake for 5-10 minutes, or just until crust is set. Remove crust from oven and cool for 5 minutes. Use rubber spatula to spread ricotta cheese over crust, leaving a half-inch border around outer edge.

3. While spaghetti is cooking, heat oil in large skillet over medium-high heat. Add sausage and cook for 5-8 minutes, or just until no pink remains. Break sausage up with the back of a spoon as it cooks. Add the onion, garlic, oregano, basil, tomato sauce, pureed tomatoes, tomato paste, vinegar, sugar, red pepper flakes, remaining salt, and black pepper to sausage. Reduce heat and simmer for 5-10 minutes. Layer sauce over ricotta, and sprinkle with remaining Parmesan cheese and the shredded Italian blend cheese. Place pan in oven and bake for 20-25 minutes, or just until heated through and cheese is melted and light golden brown. Remove from oven and allow spaghetti pie to sit for 5-10 minutes. Cut into serving-sized pieces. Pass additional shredded Parmesan cheese. Serve with a green salad and hot garlic bread or breadsticks.