Cook lasagna noodles according to package directions; drain and cool.
In a mixing bowl, combine thawed spinach, ricotta cheese, 1½ cups mozzarella, parmesan cheese, and egg until well mixed.
Spread ¼ cup filling onto each noodle; roll tightly. Place in a baking dish with 1 cup tomato sauce at the bottom. Top with remaining sauce and mozzarella.
Cover with foil and bake at 375°F for 25 minutes.