Spinach Lasagna

This is a family recipe, not sure where it originally came from.  My family recipe uses to jars of spaghetti sauce, but I prefer only one.  In Italy lasagna (or pasticcio) typically has far less sauce than in the U.S.  

Spinach Lasagna

image from tasteofhome.come

15 oz ricotta cheese or cottage cheese
1.5 c. shredded mozzarella
1 egg, beaten
1.25 c. frozen spinach or spinach puree
1/2 tsp. salt
1/8 tsp. pepper
3/4 tsp. oregano
1 jar (15.5 oz) spaghetti sauce 
1 c. water
In a large bowl, mix ricotta, 1 c. mozzarella, egg, spinach, salt, pepper and oregano.  In a greased 13" x 9" x 2" pan layer 1/2 c. spaghetti sauce and 1/3 of noodles and 1/2 of cheese mixture.  Repeat three layers .  Top with remaining noodles and sauce and sprinkle with remaining mozzarella on top.  Pour water around edges and cover tightly with foil.  Bake at 350 degrees for 1 hr 15 min.  Let stand for 15 minutes before serving.