Combine first 3 ingredients in a medium bowl; stir well, and set aside.
Spread 1/2 cup spaghetti sauce in a 13- x 9- x 2-inch baking dish. Place 3 noodles over sauce; spoon one-third of spinach mixture over noodles. Top with one-third of remaining spaghetti sauce, 1/2 cup mozzarella cheese, and 2 tablespoons Parmesan cheese. Repeat procedure twice with remaining noodles, spinach mixture, spaghetti sauce, 1 cup mozzarella, and remaining Parmesan cheese. Top with remaining 1/2 cup mozzarella cheese. Bake, uncovered, at 350° for 30 to 35 minutes or until thoroughly heated. Let stand 10 minutes.