Preheat oven to 350 degrees F (175 degrees C). Grease a 9 x 13 baking dish. Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente; drain.
While pasta is cooking, in medium saucepan, cook onions in oil over medium heat. Season with salt and pepper, and cook until brown and soft.
In very large mixing bowl, combine pasta, onions, eggs, bread crumbs and salt and pepper to taste. Mix thoroughly. Pour into baking dish and sprinkle paprika over the top. Sprinkle with oil, if desired, and bake 50 to 60 minutes, until top is crispy and golden.