String Pie
["1 lb. ground beef", "1/2 c. chopped onion", "1 jar spaghetti sauce (or more depending on your taste)", "8 oz spaghetti (cooked, drained, hot)", "1/3 c. parmesan cheese", "15 oz container ricotta cheese", "1/2 c. or more shredded mozzarella cheese", "2 eggs, beaten", "2 Tbsp. melted butter"]
["Preheat oven to 350\u00b0.", "Cook spaghetti and drain.", "Cook beef and onion till brown; drain.", "Stir in spaghetti sauce."]
["ground beef", "onion", "sauce", "parmesan cheese", "ricotta cheese", "mozzarella cheese", "eggs", "butter"]