Heat oven to 350 degrees F.
Use 9-inch cast-iron skillet for pie, or cover outside of 8- or 9-inch springform pan with foil. Coat bottom and 1 inch up side of inside of skillet or springform pan with cooking spray. Sprinkle with bread crumbs.
Mix cooked spaghetti with 1-1/2 cups of the sauce in a medium-size bowl. Mix in eggs. Transfer to prepared skillet or pan.
Bake in 350 degree F oven 40 minutes for skillet, or 45 minutes for springform pan, or until eggs are set and knife inserted near center comes out clean. Using thin metal spatula, loosen pie from sides of pan; remove from skillet or remove springform.
Meanwhile, heat remaining 1/2 cup sauce in saucepan.
Cut pie into quarters and serve with sauce and grated cheese.