3 cups (12 ounces) shredded mozzarella cheese, divided into 2 cup and 1 cup portions
1 container (16 ounces) ricotta or cottage cheese
9 lasagna noodles
2 (15.5 ounces) cans spinach, drained
Preheat oven to 375 degrees Fahrenheit. Cook lasagna noodles according to package directions.
Combine 2 cups mozzarella cheese, ricotta (or cottage) cheese, and parmesan cheese in a medium bowl.
Heat spaghetti sauce in saucepan.
Pour 3/4 cups sauce in 13x9-inch pan; arrange 3 pieces pasta over sauce.
Pour 1/2 cup sauce over pasta; spread 1 can spinach over sauce; spread with half cheese mixture. Lay down 3 more pieces of pasta and repeat layers. Top with pasta and remaining sauce; sprinkle with additional parmesan cheese, if desired.
Cover with foil and bake 1 hour. Sprinkle with remaining mozzarella cheese. Let stand for 10 minutes before serving.