Preheat oven to 350 degree F.
Break vermicelli into thirds, and cook according to package directions. Drain and set aside. Meanwhile, saute onion and garlic in oil until tender. Add pasta, 1/2 cup Romano cheese, and 1 egg; mix well. Press into a greased 9-inch springform pan.
Separate yolks and whites of remaining 2 eggs. Combine yolks, ricotta cheese, spinach, salt, and remaining 1/2 cup Romano cheese. Spread over pasta layer.
In small mixing bowl, beat egg whites until stiff but not dry; fold in 1-1/2 cups spaghetti sauce. Pour over spinach layer. Bake 50 to 60 minutes, until set. Let stand 10 minutes, then remove sides of pan and cut into wedges. Heat remaining sauce and serve with pie.